Case History, Vital Signs and the Physical Examination

Most diagnoses are made, or at least strongly suspected, before a single lab test or film is ordered: a careful history points to the answer in the large majority of cases, and the physical examination confirms or refutes it. In a chiropractic office these skills separate a mechanical back pain from an aneurysm, a pyelonephritis or a metastasis.

Section 1The case history

The history builds a differential diagnosis, a ranked list of plausible explanations, and gathers the facts that move each candidate up or down the list. It also establishes rapport and identifies patients who should not be treated in the office at all.

Components of the comprehensive history

A new patient deserves the full structure; a follow up may need only a focused history.

1. Identifying data and source: age, sex, occupation, who is giving the history (patient, relative, interpreter, records) and how reliable that source appears.
2. Chief complaint (CC): the main reason for the visit, recorded in the patient's own words and kept short, for example "my low back has been killing me for three days." It is not a diagnosis.
3. History of present illness (HPI): a chronological, detailed account of the chief complaint, organized with a mnemonic such as OPQRST or OLDCARTS, including associated symptoms, pertinent positives and pertinent negatives, prior episodes, prior care and its results.
4. Past medical history (PMH): childhood and adult illnesses, surgeries, hospitalizations, prior injuries and accidents, obstetric history, current medications (prescription, over the counter, supplements), allergies with the type of reaction, and immunizations.
5. Family history (FH): age and health or cause and age at death of parents, siblings and children; heritable conditions such as early coronary disease, diabetes, hypertension, cancer, rheumatoid arthritis, ankylosing spondylitis, osteoporosis and bleeding disorders.
6. Personal and social history (SH): tobacco (in pack years, packs per day multiplied by years smoked), alcohol (quantity and a screen such as CAGE), recreational and injection drug use, occupation and ergonomics, exercise, diet, sleep, stress, living situation, sexual history when relevant, and travel.
7. Review of systems (ROS): a head to toe checklist of symptoms in each body system that the patient may not have connected to the complaint.

Characterizing a symptom: OPQRST and OLDCARTS

Every symptom, and pain in particular, has a set of attributes that together form a recognizable pattern. Two mnemonics are widely taught and cover the same ground.

OLDCARTS expands the same idea: Onset, Location, Duration, Character, Aggravating and Alleviating factors, Radiation, Timing and Severity. Whatever mnemonic you use, always add associated symptoms (fever, weight loss, numbness, weakness, bowel or bladder change, nausea, dyspnea), previous episodes, and treatment so far with its effect. A pertinent negative is a symptom the patient denies that matters to the differential: "no saddle numbness, no urinary retention" is as important in a back pain note as anything the patient does report.

Pain intensity is recorded on a numeric rating scale (0 to 10) or a 100 mm visual analog scale; disability questionnaires are covered in Chapter 4.

The review of systems

The ROS is a head to toe symptom inventory, asked after the HPI, that catches what the patient did not volunteer: constitutional symptoms (fever, chills, night sweats, fatigue, weight change), then each organ system. Positive answers relevant to the complaint move into the HPI. The constitutional, gastrointestinal, genitourinary, vascular and neurologic sections are the ones most likely to reveal that a "back pain" is not musculoskeletal.

Red flag questions

A red flag is a history or examination feature associated with serious pathology that needs further investigation or referral. Red flags do not prove serious disease (many are individually weak predictors), but their presence changes the plan. Every new spinal patient should be screened for them, and the screening should be documented.

Interviewing and communication

The interview starts with open ended questions ("Tell me about your back") that let the patient tell the story, then narrows to closed questions ("Does the pain go below the knee?") to test specific hypotheses. Avoid leading questions ("The pain is worse when you cough, isn't it?") and compound questions that ask two things at once. Useful techniques include facilitation ("go on"), reflection (repeating the patient's words), clarification ("what do you mean by dizzy?"), empathic responses and a closing summarization. With a language barrier, use a trained medical interpreter rather than a relative and speak directly to the patient.

Documentation

The record is a legal document and a communication tool. Most visits are recorded in SOAP format.

Records are legible, dated, signed and timely. Errors are corrected with a single line through the entry, leaving it readable, with date and initials; entries are never erased or backdated. Informed consent (nature of the procedure, material risks, alternatives, chance to ask questions) is documented before treatment.

Section 2Vital signs and general survey

An abnormal vital sign is often the first clue that a patient is sicker than they appear.

The general survey

The general survey starts as the patient walks in: apparent versus stated age, consciousness, distress, habitus, posture and gait, hygiene, skin color (pallor, cyanosis, jaundice), odors (alcohol, ketones, uremia) and affect. A patient with peritonitis lies still; one with renal colic writhes and cannot get comfortable.

Blood pressure technique

The difference between systolic and diastolic is the pulse pressure; mean arterial pressure is about diastolic plus one third of the pulse pressure.

1. Prepare the patient: no caffeine, exercise or smoking for 30 minutes, empty bladder, seated quietly for at least 5 minutes with back supported, feet flat on the floor and legs uncrossed, and no talking during the measurement.
2. Support the bare arm with the cuff at heart level (the midsternum).
3. Choose the correct cuff: the bladder length should encircle about 80 percent of the arm circumference and its width about 40 percent. Center the bladder over the brachial artery with the lower edge 2 to 3 cm above the antecubital crease.
4. Estimate systolic pressure by palpation: inflate while feeling the radial pulse, note where it disappears, deflate, and then inflate 20 to 30 mm Hg above that point for the auscultatory reading. This avoids being misled by an auscultatory gap.
5. Place the stethoscope bell or diaphragm lightly over the brachial artery and deflate at 2 to 3 mm Hg per second.
6. Record systolic at the first of two consecutive tapping sounds (Korotkoff phase I) and diastolic at the disappearance of sounds (phase V). Take at least two readings a minute or more apart and average them; at the first visit measure both arms and use the higher arm thereafter.

Common errors: a cuff that is too small reads falsely high (the usual error in obese or muscular arms) and one too large reads low; an arm below heart level reads high and above reads low; an unsupported back or arm, crossed legs, talking or a full bladder raise the reading; deflating too fast or missing an auscultatory gap underestimates systolic.

Blood pressure classification

The current adult classification used in the United States is based on the average of two or more properly measured readings on two or more occasions.

A reading above 180/120 with signs of acute target organ damage (chest pain, dyspnea, neurologic deficit, confusion, visual loss, papilledema, acute kidney injury) is a hypertensive emergency requiring immediate transfer. Without organ damage it is an urgency needing prompt medical care. Older references define hypertension as 140/90 or above.

A difference of more than about 10 to 15 mm Hg between arms suggests subclavian artery stenosis, aortic dissection or coarctation. Leg pressures are normally equal to or slightly higher than arm pressures; leg pressures lower than arm pressures suggest coarctation of the aorta (with radiofemoral delay) or aortoiliac disease.

Orthostatic vital signs

Measure supine after 5 minutes, then 1 and 3 minutes after standing. Orthostatic hypotension is a fall of 20 mm Hg or more systolic or 10 mm Hg or more diastolic within 3 minutes of standing. A drop with a brisk heart rate rise suggests volume depletion; a drop without a rate rise suggests autonomic failure (diabetic neuropathy, Parkinson disease) or beta blockers. A symptomatic rise of 30 or more beats per minute without hypotension defines postural orthostatic tachycardia syndrome.

Pulse

Count a full minute if irregular; an apical rate exceeding the radial rate (pulse deficit) is typical of atrial fibrillation.

Respiration

Count respirations without telling the patient, since awareness changes the rate. The normal adult rate is about 12 to 20 per minute.

Temperature

Normal oral temperature averages about 37°C (98.6°F), lowest in early morning. Rectal readings run about 0.5°C higher and axillary about 0.5°C lower. Fever is 38.0°C (100.4°F) or higher; the elderly and immunosuppressed may mount little fever even with serious infection.

Oxygen saturation

Normal SpO2 is about 95 to 100 percent; under 90 percent corresponds roughly to an arterial PO2 under 60 mm Hg. Readings are falsely normal in carbon monoxide poisoning and unreliable with poor perfusion, motion, nail polish and darker skin pigmentation.

Height, weight and BMI

Body mass index equals weight in kilograms divided by height in meters squared. Height loss over about 4 cm (1.5 inches) suggests osteoporotic compression fractures; unintentional loss of more than 5 percent of body weight in 6 to 12 months is a red flag.

Waist circumference over 40 inches (102 cm) in men or 35 inches (88 cm) in women marks increased cardiometabolic risk.

Section 3Head, eyes, ears, nose, throat and neck

Many head and neck findings are windows onto systemic disease: papilledema signals raised intracranial pressure, a Virchow node abdominal cancer, an elevated JVP right heart failure.

Head and face

Classic facies include the moon face of Cushing syndrome, the coarse features of acromegaly, the puffy face with thinned lateral eyebrows of hypothyroidism, the masked face of Parkinson disease and the malar rash of lupus sparing the nasolabial folds. Palpate the temporal arteries in older patients with new headache: tenderness, nodularity or a reduced pulse suggests giant cell arteritis, which threatens vision and calls for same day referral.

Visual acuity and visual fields

Distance acuity is tested one eye at a time with a Snellen chart at 20 feet (6 meters), with the patient's glasses on. The result is a fraction: the numerator is the testing distance and the denominator is the distance at which a normal eye can read that line. 20/40 means the patient reads at 20 feet what a normal eye reads at 40. Legal blindness in the United States is best corrected acuity of 20/200 or worse in the better eye or a visual field of 20 degrees or less. Near vision is tested with a card at about 14 inches; age related loss of near vision is presbyopia.

Visual fields are screened by confrontation, comparing the patient's field in each quadrant with the examiner's. A lesion of the optic chiasm (classically a pituitary adenoma) gives bitemporal hemianopia; lesions behind the chiasm give a contralateral homonymous defect, with macular sparing in occipital strokes (detailed in Chapter 6).

Pupils and external eye

Pupils should be equal, round and reactive to light and accommodation (PERRLA); a difference under about 1 mm is often physiologic. In the swinging flashlight test: if both pupils dilate when the light swings onto one eye, that eye has an afferent defect, the Marcus Gunn pupil or relative afferent pupillary defect (optic nerve disease). Also know the Argyll Robertson pupil (small, irregular, accommodates but does not react to light) of neurosyphilis; Horner syndrome (ipsilateral ptosis, miosis, anhidrosis; Pancoast tumor, carotid dissection) and the fixed dilated pupil of third nerve compression (uncal herniation, posterior communicating artery aneurysm).

On the external eye, look for xanthelasma and early arcus (hyperlipidemia), Kayser Fleischer rings (Wilson disease), scleral icterus (bilirubin over about 2.5 mg/dL) and exophthalmos (Graves disease). A painful red eye with reduced vision, a fixed mid dilated pupil and a hazy cornea is acute angle closure glaucoma, an emergency.

Ophthalmoscopy

Use your right eye for the patient's right eye, in a dark room. Find the red reflex from about 15 inches, move in to the optic disc, follow the vessels to each quadrant, and finish at the macula. The normal disc is round, yellow orange, with sharp margins and a central physiologic cup less than half the disc diameter (cup to disc ratio under about 0.5). Arteries are lighter and narrower than veins (artery to vein ratio about 2 to 3), and spontaneous venous pulsations at the disc indicate normal intracranial pressure.

Ears and hearing

Before inserting the otoscope, pull the auricle up and back in adults (down and back in infants and young children) to straighten the canal, and use the largest speculum that fits comfortably. Pain on moving the auricle or pressing the tragus suggests otitis externa; pain without that tenderness suggests middle ear disease. The normal tympanic membrane is translucent and pearly gray, with the handle and short process of the malleus visible and a cone of light reflecting anteroinferiorly (at about 5 o'clock in the right ear and 7 o'clock in the left).

Tuning fork tests, ideally with a 512 Hz fork, separate conductive loss (outer or middle ear: wax, otitis media, otosclerosis, perforation) from sensorineural loss (cochlea or cochlear nerve: presbycusis, noise, ototoxic drugs, Meniere disease, acoustic neuroma).

• Weber test: the vibrating fork is placed on the vertex or midforehead and the patient says where the sound is heard. Normally it is heard in the midline. In a conductive loss the sound lateralizes to the affected ear (the ear is shielded from room noise and bone conduction is relatively enhanced); in a sensorineural loss it lateralizes to the good ear.
• Rinne test: the fork is placed on the mastoid process until the patient no longer hears it, then held near the ear canal. Normally air conduction is greater than bone conduction (about twice as long), a "positive" Rinne. In a conductive loss bone conduction equals or exceeds air conduction in the affected ear (a "negative" Rinne). In a sensorineural loss air conduction remains greater than bone, but both are reduced.

Nose and sinuses

Look for septal perforation (cocaine, granulomatosis with polyangiitis), the pale boggy mucosa of allergic rhinitis and nasal polyps (asthma, aspirin sensitivity, cystic fibrosis in a child). Most nosebleeds arise from Kiesselbach plexus on the anterior septum. Frontal and maxillary sinuses are palpated or percussed for tenderness and transilluminated; reduced glow suggests fluid. Sinus tenderness with purulent discharge, maxillary toothache, and symptoms lasting more than 10 days or worsening after initial improvement ("double sickening") suggests bacterial sinusitis.

Mouth and throat

Inspect every surface including the underside of the tongue and floor of mouth, and palpate any lesion. Tonsils are graded 1+ (within the pillars) to 4+ (touching).

The mouth exam also tests cranial nerves. When the patient says "ah," the uvula and soft palate pull away from the side of a vagus (CN X) lesion, toward the strong side. On protrusion, the tongue deviates toward the side of a hypoglossal (CN XII) lower motor neuron lesion, pushed by the intact genioglossus.

Lymph nodes of the head and neck

Palpate with the finger pads, comparing sides, in a consistent sequence: preauricular, posterior auricular, occipital, tonsillar (jugulodigastric), submandibular, submental, superficial cervical, posterior cervical, deep cervical chain and supraclavicular. For each node note size, shape, consistency, tenderness, mobility and whether nodes are matted together.

A hard left supraclavicular node, the Virchow node (Troisier sign), suggests metastasis from an abdominal or pelvic cancer, classically gastric, via the thoracic duct. Generalized lymphadenopathy raises mononucleosis, HIV, lymphoma and leukemia.

Thyroid

Palpate the thyroid as the patient swallows; a normal gland is barely palpable. A diffusely enlarged gland with a bruit suggests Graves disease; a firm, rubbery, nontender goiter suggests Hashimoto thyroiditis; a tender gland after a viral illness suggests subacute (de Quervain) thyroiditis; and a single hard, fixed nodule with cervical lymphadenopathy or hoarseness suggests carcinoma.

Carotid arteries and jugular venous pressure

Palpate the carotids one at a time, low in the neck, away from the carotid sinus. Auscultate with the bell during a held breath; a bruit suggests atherosclerotic stenosis, though an aortic murmur can radiate to the neck.

The jugular venous pressure (JVP) estimates right atrial pressure. With the head of the table raised 30 to 45 degrees, identify the right internal jugular pulsation and measure the vertical distance from the sternal angle to the top of the pulsation. A height over 3 to 4 cm above the sternal angle (equivalent to a right atrial pressure over about 8 to 9 cm H2O, since the right atrium lies about 5 cm below the angle) is elevated: right heart failure, fluid overload, tricuspid disease, constrictive pericarditis, tamponade or superior vena cava obstruction. A sustained JVP rise with abdominal pressure is a positive hepatojugular reflux (right sided failure). A paradoxical rise in JVP on inspiration is Kussmaul sign (constrictive pericarditis, restrictive cardiomyopathy).

In the jugular waveform, the a wave is atrial contraction and the v wave atrial filling against a closed tricuspid. Absent a waves mean atrial fibrillation; large cannon a waves mean the atrium is contracting against a closed tricuspid valve (complete heart block, ventricular tachycardia); giant v waves mean tricuspid regurgitation.

Section 4Thorax, heart and lungs

The chest exam follows inspection, palpation, percussion and auscultation, posterior chest first.

Landmarks

The sternal angle marks the second rib and the tracheal bifurcation (T4 to T5). Posteriorly, the inferior scapular angle lies at about the seventh rib, and the lung bases at about T10 on expiration and T12 on deep inspiration.

Inspection and palpation

The normal anteroposterior diameter is about half the lateral; a barrel chest (ratio near 1 to 1) suggests emphysema. Note pectus deformities, kyphoscoliosis, accessory muscle use, unilateral lag (pneumonia, effusion, rib fracture) and paradoxical movement (flail chest). Clubbing suggests lung cancer, bronchiectasis, fibrosis, cyanotic heart disease or endocarditis, not uncomplicated COPD.

Chest expansion measured by tape at the fourth intercostal space normally exceeds about 5 cm; expansion under about 2.5 cm is a classic finding in ankylosing spondylitis. Tactile fremitus is the palpable vibration transmitted to the chest wall when the patient says "ninety nine": sound travels better through solid tissue than through air or fluid, so fremitus is increased over consolidation and decreased or absent over effusion, pneumothorax, emphysema, a thick chest wall or an obstructed bronchus.

Percussion

Percuss symmetrically, side to side, avoiding the scapulae.

Normal diaphragmatic excursion is about 3 to 6 cm.

Breath sounds and voice sounds

Normal vesicular sounds (soft, low, inspiration longer than expiration) are heard over most lung; bronchovesicular sounds near the main bronchi; bronchial sounds (loud, high, expiration longer) over the manubrium.

When bronchial breath sounds are heard over the peripheral lung, air filled alveoli have been replaced by fluid or tissue that conducts sound well: consolidation. Three voice sounds confirm it: bronchophony (spoken "ninety nine" becomes louder and clearer), egophony (a spoken "ee" sounds like "ay", the E to A change) and whispered pectoriloquy (whispered words heard distinctly).

The heart: inspection and palpation

The apical impulse or point of maximal impulse (PMI) is normally in the fifth intercostal space at or just medial to the left midclavicular line, no more than about 2.5 cm in diameter, brief and tapping. A laterally displaced, diffuse impulse suggests left ventricular dilation (heart failure, regurgitant lesions); a sustained, forceful but not displaced impulse suggests left ventricular hypertrophy (hypertension, aortic stenosis). A lift or heave along the left sternal border indicates right ventricular enlargement. A thrill is a palpable vibration from a loud murmur (grade 4 or higher) and is best felt with the palm or the ball of the hand.

Auscultation areas

Use the diaphragm for high pitched sounds (S1, S2, regurgitant murmurs, rubs) and the bell, held lightly, for low pitched ones (S3, S4, mitral stenosis rumble).

Heart sounds

Splitting of S2: during inspiration, increased venous return to the right heart delays P2, so A2 and P2 separate (physiologic splitting), heard best in the pulmonic area. Wide splitting (present in both phases, wider on inspiration) occurs when P2 is delayed by right bundle branch block or pulmonic stenosis. Fixed splitting that does not vary with respiration is the hallmark of an atrial septal defect. Paradoxical (reversed) splitting, heard on expiration and narrowing on inspiration, means A2 is delayed: left bundle branch block, severe aortic stenosis.

Murmurs

Describe a murmur by timing, location, radiation, intensity, pitch, quality and shape. Soft midsystolic flow murmurs can be innocent; diastolic murmurs are always pathologic.

Peripheral vascular signs

Pulses are graded 0 absent, 1+ diminished, 2+ normal, 3+ increased, 4+ bounding; capillary refill is normally under about 2 seconds.

Pitting edema is graded 1+ to 4+. Bilateral edema suggests heart failure, nephrotic syndrome, cirrhosis or venous insufficiency; unilateral calf swelling, warmth and tenderness suggests deep vein thrombosis. The Homans sign (calf pain on passive dorsiflexion) is neither sensitive nor specific and should not be relied upon; a pretest probability score (Wells) plus D dimer or duplex ultrasound is the accepted approach.

The ankle brachial index (ABI) divides the higher ankle systolic pressure (dorsalis pedis or posterior tibial, measured by Doppler) by the higher brachial systolic pressure. Values of 1.0 to 1.4 are normal, 0.91 to 0.99 borderline, 0.90 or less diagnostic of peripheral arterial disease, under about 0.4 critical ischemia, and over 1.4 indicates noncompressible, calcified vessels (diabetes, chronic kidney disease). Acute limb ischemia presents with the six Ps: pain, pallor, pulselessness, paresthesia, paralysis and poikilothermia (coldness), and is an emergency.

Section 5Abdominal, rectal and male urogenital examination

Abdominal and pelvic organs refer pain to the back, flank, groin and shoulder, so the abdominal exam belongs in the workup of many spinal complaints.

Regions and sequence

The abdomen is divided into four quadrants by a vertical midline and a horizontal line through the umbilicus, or into nine regions (hypochondriac, epigastric, lumbar, umbilical, inguinal and hypogastric).

The patient lies supine with knees slightly flexed; examine the painful area last. The sequence is inspection, auscultation, percussion, palpation: auscultation comes before percussion and palpation because manipulating the bowel can alter bowel sounds.

Inspection and auscultation

Note purple striae (Cushing syndrome), caput medusae (portal hypertension) and visible pulsation (normal when thin, or an aneurysm). Bruising around the umbilicus (Cullen sign) or in the flanks (Grey Turner sign) indicates retroperitoneal hemorrhage, classically from hemorrhagic pancreatitis, also from ruptured ectopic pregnancy or aneurysm.

Normal bowel sounds occur roughly 5 to 35 per minute; listen at least 2 minutes before calling them absent (ileus, peritonitis). High pitched, tinkling, rushing sounds suggest early mechanical obstruction. Listen for bruits over the aorta, renal arteries (renal artery stenosis with hypertension), iliac and femoral arteries.

Percussion

Tympany predominates; dullness lies over solid organs, masses, fluid and a full bladder. Liver span in the right midclavicular line is normally about 6 to 12 cm (larger in tall people and men). The spleen is percussed in Traube space (the left lower anterior chest, normally tympanic) and at the lowest left interspace in the anterior axillary line (Castell sign: dullness there on deep inspiration suggests splenomegaly). Ascites is suggested by shifting dullness and a fluid wave. Costovertebral angle tenderness is tested by a firm fist percussion over the angle between the twelfth rib and the spine (Murphy punch); marked pain suggests pyelonephritis or other renal disease, though muscle soreness can produce mild tenderness.

Palpation

Light palpation precedes deep palpation. Voluntary guarding lessens when the patient relaxes or exhales; involuntary rigidity (a boardlike abdomen) persists and indicates peritoneal inflammation.

• Liver: the edge descends to the examining hand on deep inspiration; a normal edge is soft and smooth at or just below the costal margin, while a hard, nodular edge suggests cirrhosis or metastases.
• Spleen: a spleen must be roughly two to three times its normal size before it can be felt, so a palpable spleen is abnormal (mononucleosis, portal hypertension, hematologic malignancy). A large spleen is vulnerable to rupture, so avoid deep pressure and contact sports, and avoid vigorous thoracolumbar thrusts during acute mononucleosis.
• Aorta: width over about 3 cm, or a pulsation that pushes the hands apart (expansile rather than merely transmitted), suggests an abdominal aortic aneurysm. Ultrasound is the screening test (once for men 65 to 75 who have ever smoked).

Special abdominal signs

Hernias

Examine the groin standing: invaginate scrotal skin up to the external inguinal ring and ask the patient to cough.

A hernia that cannot be reduced is incarcerated; if its blood supply is compromised it is strangulated, presenting as a tender, tense, discolored bulge with fever and signs of bowel obstruction. Strangulation is a surgical emergency.

Rectal and prostate examination

Assess the anal wink (S2 to S4) and resting sphincter tone and voluntary squeeze; reduced tone with saddle anesthesia is a sign of cauda equina syndrome.

The prostate is felt on the anterior wall. A normal gland is about the size of a walnut (roughly 2.5 cm long and 4 cm wide), rubbery, nontender and smooth, with two lateral lobes separated by a palpable median sulcus.

Male genital examination and the acute scrotum

Palpate each testis (normally 4 to 5 cm, smooth, rubbery), the posterolateral epididymis and the cord. Note paraphimosis (retracted foreskin cannot be returned, an emergency), discharge and genital ulcers (the painless, indurated chancre of primary syphilis versus the painful ulcers of chancroid and herpes). The cremasteric reflex (stroking the inner thigh raises the ipsilateral testis) tests L1 to L2. Any scrotal mass should be transilluminated with a light pressed against the scrotum in a dark room: fluid glows, solid tissue and blood do not.

Words worth knowing

Laboratory Interpretation and Special Studies

Laboratory tests turn a clinical suspicion into a number, but only a clinician who knows what each test measures, what moves it and how often it misleads can use that number well. Part II asks you to read a urinalysis, a CBC, a chemistry panel, a set of rheumatologic markers and a few special studies, and to decide what they mean for the patient in front of you. In practice, these results are often what tells a chiropractor that a "back pain" is a myeloma, a pyelonephritis or a spondyloarthropathy.

Section 1Urinalysis

The urinalysis is cheap, fast and informative about the kidneys, the urinary tract and systemic metabolism. A clean catch midstream specimen, examined within about an hour or refrigerated, avoids contamination and the breakdown of cells and casts. The exam has three parts: physical, chemical (dipstick) and microscopic.

Physical examination

Dipstick (chemical) findings

Microalbuminuria (moderately increased albuminuria), a urine albumin to creatinine ratio of 30 to 300 mg/g, is below the dipstick threshold but is the earliest marker of diabetic nephropathy and an independent cardiovascular risk factor; people with diabetes are screened annually.

Microscopic examination

The sediment is examined under low and high power. More than about 3 red cells per high power field is hematuria; more than about 5 white cells per field is pyuria. Many squamous epithelial cells indicate a contaminated sample, while renal tubular epithelial cells suggest acute tubular necrosis. Dysmorphic red cells (misshapen from passage through the glomerulus) point to glomerular bleeding; uniform cells point to the lower tract (stone, tumor, infection). Sterile pyuria (white cells without growth on culture) suggests tuberculosis, chlamydia or gonorrhea, interstitial nephritis or a stone.

Casts are cylinders of Tamm Horsfall mucoprotein formed in the distal tubule and collecting duct, so anything trapped in them came from the kidney itself. They are the most localizing finding in the sediment.

Section 2Hematology

The complete blood count

Anemia workup

Anemia is a sign, not a diagnosis. The first step is the MCV; the second is the reticulocyte count, which asks whether the marrow is responding (high: blood loss or hemolysis) or failing (low: deficiency, chronic disease, marrow disease).

Iron deficiency is the most common anemia worldwide. In a man or postmenopausal woman, iron deficiency means gastrointestinal blood loss until proven otherwise (colon cancer, ulcer, NSAID gastropathy), so it always calls for referral. Anemia of chronic disease (inflammation, infection, malignancy, rheumatoid arthritis) is driven by hepcidin, which traps iron in macrophages; it is usually normocytic but may become mildly microcytic. In thalassemia trait, the red cell count is normal or high despite microcytosis (a Mentzer index, MCV divided by RBC count, under 13 favors thalassemia); hemoglobin electrophoresis shows increased HbA2 in beta thalassemia trait.

Macrocytic anemia with hypersegmented neutrophils (six or more lobes) is megaloblastic. Vitamin B12 deficiency raises both methylmalonic acid and homocysteine, and can cause subacute combined degeneration of the dorsal columns and lateral corticospinal tracts (loss of vibration and position sense, ataxia, spasticity, paresthesias), sometimes before anemia appears. Folate deficiency raises homocysteine only and spares the nervous system. Pernicious anemia (antibodies to intrinsic factor and parietal cells), vegan diet, gastric or ileal surgery, metformin and proton pump inhibitors cause B12 deficiency.

Hemolysis is signaled by a high reticulocyte count, high LDH, high unconjugated (indirect) bilirubin and low haptoglobin. A positive direct Coombs (antiglobulin) test means antibody coated red cells: autoimmune hemolysis (lupus, CLL, drugs) or transfusion reaction.

White cell differential

Remember the order of normal frequency with "Never Let Monkeys Eat Bananas." Absolute neutrophil count under about 1,500/µL is neutropenia and under 500/µL carries severe infection risk. A very high count (over about 50,000) raises the question of leukemoid reaction versus leukemia; blasts in the peripheral blood suggest acute leukemia and require urgent referral.

Platelets and coagulation

Thrombocytopenia is a count under 150,000/µL. Surgical bleeding risk rises below about 50,000, and spontaneous bleeding (petechiae, purpura, mucosal bleeding) below about 10,000 to 20,000. Causes include immune thrombocytopenia, drugs (heparin induced thrombocytopenia, which paradoxically causes clotting), DIC, TTP, marrow failure and splenic sequestration. Thrombocytosis is usually reactive (iron deficiency, inflammation, after splenectomy) but can be a myeloproliferative neoplasm.

Factor VII has the shortest half life, so the PT is the first test to prolong with warfarin, vitamin K deficiency or early liver failure. DIC prolongs PT and aPTT, lowers platelets and fibrinogen, raises D dimer and produces schistocytes. A normal D dimer helps rule out DVT or PE when clinical probability is low; a positive one proves little.

Erythrocyte sedimentation rate

The ESR (Westergren method) measures how far red cells fall in a tube in one hour. Fibrinogen and immunoglobulins neutralize the negative surface charge of red cells, so they stack (rouleaux) and sink faster. A rough upper limit is age divided by 2 for men and (age plus 10) divided by 2 for women in mm/h. The ESR is a nonspecific marker of inflammation that rises slowly and stays up for weeks. It is elevated in infection (including osteomyelitis and discitis), inflammatory arthritis, malignancy, anemia, pregnancy, kidney disease and older age; it is very high (often over 100 mm/h) in multiple myeloma, giant cell arteritis, polymyalgia rheumatica and osteomyelitis. It is falsely low in polycythemia, sickle cell disease, spherocytosis and low fibrinogen states.

Section 3Clinical chemistry

The basic metabolic panel (electrolytes, glucose, BUN, creatinine, calcium) and the comprehensive panel (which adds the liver tests, albumin and total protein) are the most commonly ordered blood tests. Learn the reference ranges below as board values; individual laboratories vary slightly.

Electrolytes, glucose and renal function

The anion gap equals sodium minus (chloride plus bicarbonate), normally about 8 to 12. A high anion gap metabolic acidosis suggests unmeasured acids: ketoacidosis, lactic acidosis, uremia, or toxins (methanol, ethylene glycol, salicylates). A BUN to creatinine ratio over 20 suggests a prerenal cause (dehydration, heart failure) or upper GI bleeding; a ratio near 10 to 15 with both elevated suggests intrinsic renal disease.

The estimated GFR, calculated from creatinine, age and sex, stages chronic kidney disease, defined as eGFR under 60 mL/min/1.73 m2 or markers of kidney damage (such as albuminuria) for more than 3 months. Stages run from G1 (90 or more, with damage) through G3a (45 to 59), G3b (30 to 44) and G4 (15 to 29) to G5, under 15 (kidney failure). Because creatinine rises only after substantial nephron loss, a "normal" creatinine in a small elderly woman may hide a low GFR. eGFR matters for drug dosing, contrast imaging and NSAID advice.

Without unequivocal hyperglycemia, a diagnosis needs two abnormal results (the same test twice or two different tests). HbA1c reflects average glucose over the life span of the red cell, roughly the previous 2 to 3 months; it reads falsely low when red cell turnover is fast (hemolysis, blood loss, recent transfusion) and falsely high in iron deficiency. A common treatment target is under 7 percent. Fasting hypoglycemia is glucose under about 70 mg/dL; symptoms (sweating, tremor, confusion) usually appear under about 55.

Liver panel

Patterns matter more than single values. A hepatocellular pattern has transaminases raised out of proportion to ALP: viral hepatitis (ALT over AST, often in the hundreds to thousands), ischemic or acetaminophen injury (thousands), fatty liver disease (mild ALT elevation). An AST to ALT ratio over 2 suggests alcoholic liver disease. A cholestatic pattern has ALP and GGT raised out of proportion, with or without conjugated bilirubin: gallstones in the common duct, pancreatic head cancer, primary biliary cholangitis, drugs. An isolated high ALP with normal GGT points to bone.

Lipid panel

LDL is often calculated with the Friedewald equation: LDL equals total cholesterol minus HDL minus triglycerides divided by 5 (in mg/dL), which is invalid when triglycerides exceed about 400. Non HDL cholesterol (total minus HDL) captures all atherogenic particles. Secondary causes of dyslipidemia include hypothyroidism, nephrotic syndrome, diabetes, cholestasis and drugs.

Calcium, phosphorus and alkaline phosphatase

Total serum calcium is about 8.5 to 10.5 mg/dL, of which roughly 40 percent is bound to albumin. Correct for a low albumin: corrected calcium equals measured calcium plus 0.8 times (4.0 minus albumin); ionized calcium is measured directly when precision matters. Phosphorus is about 2.5 to 4.5 mg/dL. Hypercalcemia causes "stones, bones, groans and psychiatric overtones" (kidney stones, bone pain, constipation and abdominal pain, confusion and depression) plus polyuria and a short QT. More than 90 percent of hypercalcemia is due to primary hyperparathyroidism (outpatients) or malignancy (inpatients).

Cardiac markers

Cardiac troponin (I or T) is the marker of choice for myocardial injury: it begins to rise about 3 to 4 hours after onset (within 1 to 3 hours with high sensitivity assays), peaks at about 24 to 48 hours and remains elevated for 7 to 10 days or longer. A rise or fall above the 99th percentile with symptoms or ECG changes of ischemia defines myocardial infarction. CK-MB rises at 4 to 6 hours, peaks near 24 hours and returns to normal in 2 to 3 days, so it is useful for detecting reinfarction. Myoglobin rises earliest (1 to 2 hours) but is not cardiac specific. Total CK also rises with skeletal muscle injury: intramuscular injections, strenuous exercise, trauma, statin myopathy, rhabdomyolysis and muscular dystrophy. BNP (or NT-proBNP) is released by stretched ventricles; a BNP under about 100 pg/mL makes heart failure unlikely as the cause of dyspnea.

Thyroid tests

TSH (about 0.4 to 4.0 mIU/L) is the best single screening test for primary thyroid disease because pituitary output changes logarithmically with small changes in free hormone. Free T4 (about 0.8 to 1.8 ng/dL) then defines the disorder.

Section 4Serology and inflammatory and rheumatologic markers

Serologic tests are most useful when the pretest probability is moderate and the clinical picture is suggestive. Ordered indiscriminately for vague aches, they generate false positives that mislead. Always pair a marker with the history and examination.

Acute phase reactants

C reactive protein (CRP) is made by the liver under the influence of interleukin 6. It rises within 6 to 8 hours of an inflammatory stimulus, peaks at about 48 hours and falls quickly as inflammation resolves, so it tracks disease activity and treatment response better than the ESR. A standard CRP under about 1.0 mg/dL (10 mg/L) is usually normal; very high levels (over 10 mg/dL) suggest bacterial infection. High sensitivity CRP measures low levels for cardiovascular risk: under 1 mg/L low, 1 to 3 average, over 3 mg/L high risk. In septic arthritis, osteomyelitis and postoperative spinal infection, CRP and ESR are both raised, and a normal CRP makes vertebral osteomyelitis unlikely.

Rheumatoid arthritis markers

Antinuclear antibodies

The ANA, done by indirect immunofluorescence on cultured cells, is the screening test for systemic lupus erythematosus. It is positive in about 95 percent or more of SLE, so a negative ANA makes SLE very unlikely, but it is also positive at low titer in many healthy people (especially older women), in other connective tissue diseases, and with some drugs, so a positive ANA alone does not diagnose anything. Titers of 1:160 or higher are more meaningful than 1:40 or 1:80. The fluorescence pattern hints at the antigen, and specific antibody tests follow.

In active lupus, complement (C3 and C4) falls as it is consumed by immune complexes.

HLA-B27

HLA-B27 is an MHC class I allele present in about 90 percent of white patients with ankylosing spondylitis and in a majority of those with reactive arthritis, and less often in psoriatic and enteropathic axial disease. But it is also carried by roughly 6 to 8 percent of the general white population, and most carriers never develop spondyloarthritis. Its positive predictive value is therefore low in unselected patients; it is useful only when inflammatory back pain (onset before 45, insidious, morning stiffness, improvement with exercise but not rest, night pain in the second half of the night) already makes the diagnosis plausible. A negative result lowers, but does not exclude, the probability.

Uric acid and synovial fluid

Serum urate is supersaturated above about 6.8 mg/dL. Hyperuricemia is common and usually asymptomatic, and the level may be normal during an acute gout attack; the diagnosis rests on finding needle shaped, negatively birefringent monosodium urate crystals in joint fluid. Calcium pyrophosphate crystals (pseudogout) are rhomboid and weakly positively birefringent. Long term urate lowering aims for under 6 mg/dL.

PSA and tumor markers

Prostate specific antigen is organ specific but not cancer specific. A traditional cutoff is 4.0 ng/mL, with age adjusted values. PSA rises with prostate cancer, benign prostatic hyperplasia, prostatitis, urinary retention, ejaculation and instrumentation (a digital rectal exam raises it only slightly). A low percent free PSA (under about 10 percent) and a rapid rise over time favor cancer. Screening for men about 55 to 69 is an individual decision after discussion of benefits and harms. A man with a raised PSA and new low back pain needs evaluation for osteoblastic spinal metastases.

Most other tumor markers are too insensitive and nonspecific for screening and are used to support a diagnosis and monitor treatment or recurrence.

Infectious serology

The heterophile antibody (Monospot) test detects infectious mononucleosis (EBV) but may be negative in the first week and in young children; EBV viral capsid antigen IgM confirms acute infection. The antistreptolysin O titer supports recent streptococcal infection (rheumatic fever, poststreptococcal glomerulonephritis). HIV screening uses a fourth generation antigen and antibody combination test (detects p24 antigen earlier than antibody alone), confirmed by a differentiation assay. Syphilis uses a nontreponemal test (RPR or VDRL), whose titer falls with treatment and which has false positives in lupus, antiphospholipid syndrome and pregnancy, and a treponemal test (FTA-ABS or TP-PA), which stays positive for life. Lyme disease uses a two tier approach (immunoassay, then confirmation). For tuberculosis infection, the tuberculin skin test is read as induration at 48 to 72 hours (positive at 5 mm or more in HIV, close contacts and the immunosuppressed; 10 mm or more in health care workers, recent immigrants and injection drug users; 15 mm or more in people without risk factors); interferon gamma release assays are not affected by prior BCG vaccination.

Hepatitis C is screened with an antibody test; a positive result is followed by HCV RNA, since antibody persists after cleared infection.

Section 5Special studies and test logic

Reference ranges

A reference range is usually the central 95 percent of results in a healthy population (the mean plus or minus 2 standard deviations). By definition, 5 percent of healthy people fall outside it. Order 20 independent tests on a healthy person and the chance that at least one is "abnormal" is about 1 minus 0.95 to the 20th power, roughly 64 percent. Results just outside the range, in a patient without matching symptoms, are often noise; repeat or follow the trend before acting. Ranges also differ by age, sex, pregnancy, laboratory and method. A critical (panic) value is one that signals immediate danger and is phoned to the clinician.

Sensitivity, specificity and predictive values

Test performance is described with a 2 by 2 table comparing the test result with the true disease state (the reference or "gold" standard).

Two mnemonics capture the clinical use. SnNout: a highly Sensitive test, when Negative, rules out disease (few false negatives), which makes sensitive tests good for screening (D dimer, ANA, the straight leg raise for disc herniation). SpPin: a highly Specific test, when Positive, rules in disease (few false positives), which makes specific tests good for confirmation (anti-CCP, anti-Smith, the crossed straight leg raise).

Sensitivity and specificity are relatively stable properties of a test, but predictive values change with prevalence. As prevalence (pretest probability) falls, PPV falls and NPV rises; as prevalence rises, PPV rises. This is why screening a low risk population produces many false positives, and why the same positive result means more in a patient whose history already points to the disease. Moving the cutoff trades one property for the other: lowering the cutoff for a positive result raises sensitivity and lowers specificity. The receiver operating characteristic (ROC) curve plots sensitivity against 1 minus specificity across cutoffs; the larger the area under it, the better the test discriminates.

Related terms: accuracy (closeness to the true value), precision or reliability (reproducibility on repeated measurement; interexaminer reliability is often expressed as the kappa statistic), and validity (whether the test measures what it claims to). A test can be precise but inaccurate if it is consistently biased.

ECG basics

Standard ECG paper runs at 25 mm/s: one small (1 mm) box is 0.04 s and one large (5 mm) box is 0.20 s; 10 mm vertically equals 1 mV. Heart rate equals 300 divided by the number of large boxes between R waves (or 1,500 divided by small boxes); for irregular rhythms count the QRS complexes in a 6 second strip and multiply by 10.

Pulmonary function tests

Spirometry measures forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and their ratio. Lung volumes (total lung capacity, residual volume) need body plethysmography or gas dilution, and the diffusing capacity (DLCO) measures gas transfer across the alveolar capillary membrane.

Asthma shows reversibility: an increase in FEV1 of at least 12 percent and 200 mL after a bronchodilator; COPD is not fully reversible. COPD severity is graded by FEV1 percent predicted (80 or more mild, 50 to 79 moderate, 30 to 49 severe, under 30 very severe). A peak flow meter allows home monitoring of asthma.

Bone density

Dual energy x-ray absorptiometry (DXA) of the lumbar spine and hip is the standard for diagnosing osteoporosis. The T score compares the patient with the peak bone mass of young healthy adults of the same sex, in standard deviations; the Z score compares with people of the same age.

A fragility fracture of the hip or spine establishes osteoporosis regardless of T score. The Z score is used in premenopausal women, men under 50 and children; a Z score of -2.0 or lower is "below the expected range for age" and should prompt a search for secondary causes (glucocorticoids, hyperparathyroidism, hyperthyroidism, malabsorption, myeloma, hypogonadism). Lumbar DXA can be falsely elevated by osteophytes, facet arthrosis, aortic calcification and compression fractures, which is why the hip is also measured. Screening is recommended for women 65 and older and for younger postmenopausal women at increased risk; the FRAX tool estimates 10 year fracture probability to guide treatment.

Nerve conduction studies and electromyography

Nerve conduction studies (NCS) stimulate a nerve and record the response, measuring latency, amplitude (number of functioning axons) and conduction velocity (myelin), normally about 50 to 60 m/s in the arms and 40 to 50 m/s in the legs. Demyelination slows velocity, prolongs latency and may cause conduction block (carpal tunnel syndrome with prolonged median distal latency, Guillain Barré syndrome). Axonal loss reduces amplitude with near normal velocity (diabetic and toxic neuropathies). Late responses test proximal segments: the H reflex is the electrical analog of the ankle jerk and is delayed or absent in S1 radiculopathy; F waves assess motor roots.

Needle electromyography (EMG) records muscle activity at rest and with contraction. Normal resting muscle is silent. After denervation, fibrillation potentials and positive sharp waves appear, but only after about 2 to 3 weeks (earlier in paraspinal muscles, later in distal limb muscles), so EMG is usually deferred until about 3 weeks after onset. Chronic reinnervation produces large, long, polyphasic motor unit potentials with reduced recruitment; myopathy produces small, short, polyphasic potentials with early recruitment.

When to order and when to refer

Order a test when its result will change management. Testing helps most when the pretest probability is intermediate: at very low probability a positive result is likely false, and at very high probability a negative result is unlikely to dissuade you. Before ordering, ask what you will do with a positive and with a negative result. Scope of practice for ordering laboratory tests and special studies varies by jurisdiction; where it allows, the chiropractor orders tests to screen for conditions outside the scope of chiropractic care and refers when results indicate.

Communicate referrals in writing, with the findings, the reason and the urgency, and document the referral and the patient's response in the record.

Words worth knowing

Diagnosis of Internal Disorders and When to Refer

A large share of the patients who walk into a chiropractic office with back, neck, chest wall or shoulder pain have a perfectly mechanical problem, but a small and important minority have disease in the heart, lungs, gut, kidneys, blood or glands that is projecting pain onto the musculoskeletal system. The General Diagnosis domain of Part II tests whether you can recognize those patients from the history, vital signs, physical exam and basic labs, and whether you know how fast they need to be sent elsewhere. This chapter walks through the internal disorders the board returns to most often and threads a clear referral decision through every one of them.

Section 1ENT, respiratory and cardiovascular disorders

The upper airway: sinusitis and pharyngitis

Acute rhinosinusitis is overwhelmingly viral. It produces nasal congestion, purulent discharge, facial pressure that worsens on bending forward, and tenderness over the maxillary or frontal sinuses. Transillumination of a fluid filled maxillary or frontal sinus shows reduced light transmission compared with the opposite side. A bacterial cause becomes likely when symptoms persist beyond 10 days without improvement, when the illness is severe from the start (fever of 39°C or more with purulent discharge for three or four days), or when the patient improves and then worsens again ("double sickening"). Chronic sinusitis lasts 12 weeks or more. The danger of sinusitis is local spread: periorbital swelling, painful or limited eye movement, visual change, severe headache with neck stiffness, or altered mental status suggests orbital cellulitis, meningitis or cavernous sinus thrombosis, and needs emergency care.

Pharyngitis is also mostly viral. The board question is whether it could be group A beta hemolytic streptococcus (Streptococcus pyogenes). The Centor criteria award one point each for fever, tonsillar exudate, tender anterior cervical lymphadenopathy and absence of cough; the McIsaac modification adds a point for age 3 to 14 and subtracts one for age 45 or older. Higher scores justify a rapid antigen test or culture. Untreated strep can lead to acute rheumatic fever (migratory polyarthritis, carditis, Sydenham chorea, erythema marginatum, subcutaneous nodules) and poststreptococcal glomerulonephritis (cola colored urine, edema, hypertension). Antibiotics prevent rheumatic fever but not glomerulonephritis.

Infectious mononucleosis (Epstein Barr virus) causes sore throat, fever, marked fatigue and posterior cervical lymphadenopathy in adolescents and young adults, with splenomegaly in about half. The heterophile antibody (Monospot) test confirms it, and atypical lymphocytes appear on the smear. Contact sports and forceful abdominal or thoracic manipulation are avoided for at least three to four weeks because the enlarged spleen can rupture; left upper quadrant pain referred to the left shoulder (Kehr sign) in such a patient is an emergency. Two upper airway emergencies deserve memorizing: peritonsillar abscess (severe unilateral throat pain, "hot potato" muffled voice, trismus, uvula deviated away from the swollen side) and epiglottitis (rapid onset, drooling, inability to swallow, inspiratory stridor, tripod posture). Never examine the throat of a child you suspect has epiglottitis; call emergency services.

Obstructive lung disease: asthma and COPD

Asthma is chronic airway inflammation with reversible bronchoconstriction and airway hyperresponsiveness. Symptoms are episodic wheeze, chest tightness, dyspnea and cough (often at night or early morning) triggered by allergens, exercise, cold air, infections, smoke, aspirin or beta blockers. Spirometry shows obstruction (reduced FEV1/FVC) that improves by at least 12 percent and 200 mL in FEV1 after a bronchodilator. A severe attack shows use of accessory muscles, inability to speak in full sentences, pulsus paradoxus, tachycardia and falling peak flow. A "silent chest" (no wheeze because almost no air is moving), cyanosis, confusion or exhaustion signals impending respiratory failure and needs emergency services.

Chronic obstructive pulmonary disease is persistent, largely irreversible airflow limitation, diagnosed when the post bronchodilator FEV1/FVC is below 0.70. Cigarette smoking is the main cause. Chronic bronchitis is defined clinically as a productive cough for at least three months in each of two consecutive years; patients are classically hypoxemic, cyanotic and edematous from cor pulmonale ("blue bloaters"). Emphysema is destruction of alveolar walls with loss of elastic recoil; patients are thin, tachypneic, breathe through pursed lips, have a barrel chest with increased AP diameter, hyperresonant percussion, decreased breath sounds and a low flat diaphragm on chest film ("pink puffers"). Centriacinar emphysema with upper lobe predominance is typical of smoking; panacinar emphysema in the lower lobes of a young nonsmoker suggests alpha 1 antitrypsin deficiency, which can also cause liver disease.

Pneumonia, effusion, pneumothorax and pulmonary embolism

Community acquired pneumonia presents with fever, chills, cough with sputum, pleuritic chest pain and dyspnea. Over a lobar consolidation the exam finds dullness, increased tactile fremitus, bronchial breath sounds, crackles, egophony (spoken "E" heard as "A"), bronchophony and whispered pectoriloquy, because solid lung transmits sound better than air filled lung. Streptococcus pneumoniae is the most common bacterial cause (rusty sputum, lobar pattern); Mycoplasma pneumoniae causes "walking" atypical pneumonia in young adults; Klebsiella causes currant jelly sputum in alcoholics; Legionella is linked to contaminated water systems, with diarrhea and hyponatremia. The CURB 65 score (Confusion, Urea over 7 mmol/L, Respiratory rate 30 or more, Blood pressure under 90 systolic or 60 diastolic, age 65 or older) estimates severity; a score of 2 or more generally means hospital care.

Spontaneous pneumothorax classically strikes a tall, thin young man (rupture of an apical bleb) with sudden unilateral pleuritic chest pain and dyspnea. Tension pneumothorax (hypotension, distended neck veins, tracheal shift away from the affected side) is immediately life threatening.

Pulmonary embolism usually arises from a deep vein thrombosis of the leg or pelvis. Risk follows Virchow triad: venous stasis (immobility, long travel, recent surgery, casting), hypercoagulability (malignancy, pregnancy, estrogen therapy, inherited thrombophilia such as factor V Leiden) and endothelial injury. The typical picture is sudden dyspnea, pleuritic chest pain, tachycardia, tachypnea, sometimes hemoptysis or syncope, often with a swollen, tender calf. The Wells score estimates pretest probability; a negative D dimer helps exclude PE in low risk patients, and CT pulmonary angiography confirms it. The Homans sign (calf pain on passive dorsiflexion) is neither sensitive nor specific and should not be used to rule DVT in or out. Suspected PE is an emergency. Suspected DVT without chest symptoms needs same day evaluation with duplex ultrasound, and the affected limb should not be massaged.

Hypertension

Blood pressure is measured after five minutes of seated rest, back supported, feet flat, arm supported at heart level, with a cuff whose bladder encircles about 80 percent of the arm. A cuff that is too small overestimates the reading. Diagnosis rests on the average of at least two readings on at least two occasions, ideally confirmed by home or ambulatory monitoring to exclude white coat hypertension.

About 90 percent of hypertension is primary (essential). Suspect a secondary cause when hypertension begins before age 30 or after 55, is resistant to three drugs, or comes with clues: an abdominal bruit and rising creatinine with ACE inhibitors (renal artery stenosis, fibromuscular dysplasia in young women, atherosclerosis in older adults); episodic headache, sweating and palpitations (pheochromocytoma); hypokalemia (primary aldosteronism); moon face and striae (Cushing syndrome); loud snoring and daytime sleepiness (obstructive sleep apnea); or higher pressure in the arms than the legs with delayed femoral pulses and rib notching on chest film (coarctation of the aorta). Long standing hypertension damages target organs: left ventricular hypertrophy, heart failure, stroke, chronic kidney disease, retinopathy (arteriolar narrowing, AV nicking, flame hemorrhages, cotton wool spots, and papilledema in severe disease).

A reading in the crisis range with no signs of acute organ damage is called hypertensive urgency and needs prompt (same day) medical contact. The same reading with chest pain, dyspnea, neurological deficit, confusion, severe headache, visual loss or papilledema is a hypertensive emergency and requires emergency services. Do not perform high velocity manipulation on a patient in the crisis range.

Coronary artery disease and heart failure

Stable angina is predictable substernal pressure, squeezing or tightness provoked by exertion, cold or emotion, lasting a few minutes and relieved by rest or nitroglycerin. It may radiate to the left arm, jaw, neck, epigastrium or between the shoulder blades. A patient who clenches a fist over the sternum to describe the pain (Levine sign) is describing ischemia. Acute coronary syndrome includes unstable angina (new onset, at rest, or a crescendo pattern), non ST elevation MI and ST elevation MI. Myocardial infarction pain typically lasts more than 20 minutes, is not relieved by rest, and comes with diaphoresis, nausea, dyspnea and a sense of doom. Women, diabetics and older adults more often have atypical presentations: fatigue, dyspnea, nausea, epigastric discomfort or isolated jaw, arm or upper back pain. Diagnosis rests on the ECG and cardiac troponin. Any suspected acute coronary syndrome means calling emergency services; the patient should not drive.

Chest wall pain from a costochondral or costovertebral problem is reproduced by palpation or a specific movement, is sharp and localized, and is unrelated to exertion. Costochondritis (tender costochondral junctions without swelling) and Tietze syndrome (tender, swollen upper costal cartilage) are common benign causes. Reproducible tenderness lowers, but never eliminates, the probability of a cardiac cause; if the history sounds ischemic, refer regardless.

Heart failure means the heart cannot pump enough blood to meet demand at normal filling pressures. Left sided failure backs fluid into the lungs: exertional dyspnea, orthopnea (needs more pillows), paroxysmal nocturnal dyspnea, basilar crackles, an S3 gallop and a displaced apical impulse. Right sided failure, most often caused by left sided failure, backs fluid into the systemic veins: jugular venous distension, positive hepatojugular reflux, hepatomegaly, ascites and bilateral dependent pitting edema. The New York Heart Association classes describe function: I, no limitation; II, symptoms with ordinary activity; III, symptoms with less than ordinary activity; IV, symptoms at rest. BNP (B type natriuretic peptide) is elevated.

Aortic aneurysm and dissection

An abdominal aortic aneurysm (AAA) is an infrarenal aorta dilated to 3 cm or more. Risk factors are age over 65, male sex, smoking (the strongest modifiable factor), hypertension, atherosclerosis and a family history. Most are asymptomatic and are found as a pulsatile, expansile midline mass above the umbilicus, on ultrasound, or as curvilinear calcification anterior to the lumbar spine on a lateral lumbar radiograph. A one time screening ultrasound is recommended for men aged 65 to 75 who have ever smoked. Rupture risk climbs steeply above 5.5 cm, the usual threshold for repair, and with rapid growth. An expanding or leaking aneurysm causes deep, boring low back, flank or abdominal pain that does not change with position; frank rupture produces the triad of severe pain, hypotension and a pulsatile mass. A patient with a known AAA and new back pain is sent to the emergency department, and deep abdominal palpation and lumbar manipulation are avoided in anyone with a known aneurysm larger than about 4 cm unless cleared by the vascular team.

Aortic dissection is a tear in the intima that lets blood split the media and form a false lumen. The pain is sudden, maximal at onset, and described as tearing or ripping, felt in the anterior chest (ascending) or the interscapular back (descending), sometimes migrating as the dissection extends. Clues are a difference of more than 20 mmHg in systolic pressure between the arms, pulse deficits, a new aortic regurgitation murmur, stroke symptoms and a widened mediastinum on chest film. Risk factors are chronic hypertension (most common), Marfan and Ehlers Danlos syndromes, bicuspid aortic valve, cocaine use, pregnancy and prior cardiac surgery. The Stanford classification drives treatment (Figure 3.1).

Peripheral arterial disease

Peripheral arterial disease (PAD) is atherosclerotic narrowing of the leg arteries, strongly linked to smoking and diabetes. Its hallmark is intermittent claudication: reproducible cramping or aching in the calf (or thigh and buttock with aortoiliac disease) brought on by a predictable walking distance and relieved within a few minutes by simply standing still. Signs include diminished or absent pedal pulses, cool shiny hairless skin, thickened nails, delayed capillary refill, pallor on elevation and dependent rubor. The ankle brachial index (ABI) divides ankle systolic pressure by the higher arm systolic pressure: 1.0 to 1.4 is normal, 0.90 or less confirms PAD, under about 0.4 indicates severe disease, and over 1.4 means calcified, noncompressible vessels (often diabetes) that make the test unreliable. Critical limb ischemia causes rest pain in the forefoot at night that is eased by hanging the leg over the bed, plus ulcers or gangrene. Acute limb ischemia from embolism shows the six Ps: pain, pallor, pulselessness, paresthesia, paralysis and poikilothermia (a cold limb), and is an emergency.

Section 2Blood, lymphatic and immunological disorders

Anemia

Anemia is a hemoglobin below about 13.5 g/dL in men and 12 g/dL in women. Symptoms reflect reduced oxygen delivery and its compensation: fatigue, exertional dyspnea, palpitations, headache, pallor of the conjunctivae and palmar creases, tachycardia and a soft flow murmur. The first laboratory step is the mean corpuscular volume (MCV), which sorts anemia into three groups (Figure 3.2).

Iron deficiency anemia is the most common anemia worldwide. In a menstruating woman it usually reflects menstrual loss, but in a man or a postmenopausal woman it is presumed to be gastrointestinal blood loss (including colon cancer) until proven otherwise, and needs referral for evaluation. Signs include koilonychia (spoon nails), angular cheilitis, glossitis and pica (craving ice or clay). Ferritin is low, total iron binding capacity is high and the smear shows small pale (microcytic, hypochromic) cells. Thalassemias produce microcytosis with normal or high iron; severe beta thalassemia causes marrow expansion with a "hair on end" skull and widened medullary spaces.

Vitamin B12 deficiency is classically due to pernicious anemia (autoantibodies against intrinsic factor or parietal cells), but also follows gastrectomy, ileal resection or Crohn disease, a strict vegan diet, and long term metformin or acid suppression. It causes megaloblastic anemia with hypersegmented neutrophils and, importantly, subacute combined degeneration of the dorsal columns (loss of vibration and position sense, positive Romberg) and lateral corticospinal tracts (weakness, spasticity, upgoing toes), plus peripheral neuropathy and cognitive change. The neurological damage can occur without anemia and becomes permanent if treatment is delayed. Methylmalonic acid and homocysteine are both raised in B12 deficiency; in folate deficiency only homocysteine rises and there are no neurological findings. Giving folate alone to a B12 deficient patient can correct the blood picture while the neuropathy progresses.

Sickle cell disease (autosomal recessive, glutamic acid replaced by valine at position 6 of beta globin) causes chronic hemolysis and painful vaso occlusive crises. Bone infarcts produce H shaped ("Lincoln log") vertebrae from central endplate depression, avascular necrosis of the femoral and humeral heads, and dactylitis in children. Patients are prone to Salmonella osteomyelitis because of autosplenectomy, although Staphylococcus aureus is still common.

Leukemias, lymphomas and multiple myeloma

Leukemias replace the marrow with malignant cells, causing the triad of marrow failure: anemia (fatigue, pallor), neutropenia (fevers and infections) and thrombocytopenia (petechiae, bruising, bleeding gums), often with bone pain from marrow expansion. Lymphomas are malignancies of lymphoid tissue that usually present as painless lymphadenopathy, sometimes with B symptoms: fever, drenching night sweats and unintended weight loss of more than 10 percent of body weight in six months.

Multiple myeloma is the most common primary malignant tumor of bone in adults and a favorite board topic because it presents as back pain. The mnemonic CRAB captures its damage: hyperCalcemia, Renal failure (light chains clog the tubules), Anemia and Bone lesions. The pain is deep, persistent and present at rest and at night, often in an older adult with fatigue, recurrent infections and an unexplained very high ESR. Radiographs show multiple punched out lytic lesions (the "raindrop" skull), diffuse osteopenia and vertebral compression fractures; the vertebral pedicles are often spared early, unlike metastatic carcinoma, which tends to destroy the pedicle (the "winking owl" sign on an AP film). Because myeloma lesions are purely lytic with little osteoblastic response, a bone scan is often normal (cold); a skeletal survey, low dose whole body CT, or MRI is used instead. Serum and urine protein electrophoresis show the monoclonal protein.

Bleeding and clotting disorders

The pattern of bleeding tells you where the defect is. Platelet disorders (thrombocytopenia, platelet dysfunction from aspirin or uremia, von Willebrand disease) cause mucocutaneous bleeding: petechiae, purpura, nosebleeds, gum bleeding, heavy menses and prolonged oozing from cuts. Coagulation factor disorders (hemophilia, liver disease, vitamin K deficiency, anticoagulant drugs) cause deep bleeding: hemarthroses, muscle hematomas and delayed bleeding after trauma or surgery. Hemophilia A (factor VIII) and hemophilia B (factor IX) are X linked recessive, so they affect males; recurrent knee, ankle and elbow hemarthroses lead to hemophilic arthropathy with widened intercondylar notch and squared patella on radiographs. Von Willebrand disease is the most common inherited bleeding disorder.

Patients taking warfarin (monitored by INR, therapeutic range usually 2 to 3) or direct oral anticoagulants (apixaban, rivaroxaban, dabigatran) bruise and bleed more easily, and anticoagulation is a recognized risk factor for spinal epidural hematoma. Forceful soft tissue work and high velocity thrust are modified or avoided in anticoagulated patients and in those with severe thrombocytopenia or hemophilia. New back pain with rapidly developing leg weakness in an anticoagulated patient is an emergency.

Lymphadenopathy

Most enlarged lymph nodes are reactive to a nearby infection: they are tender, soft, mobile and smaller than about 1 cm, and they shrink within a few weeks. Features that raise concern for malignancy are hard, rubbery or matted nodes fixed to surrounding tissue, size over about 1.5 to 2 cm, painless and progressive growth, persistence beyond four to six weeks, generalized lymphadenopathy, age over 40, B symptoms, and above all a supraclavicular location. A left supraclavicular node (Virchow node, Troisier sign) suggests metastatic abdominal cancer, especially gastric; a right supraclavicular node drains the mediastinum, lungs and esophagus. Painless, firm axillary nodes in a woman call for breast evaluation. A suspicious node is referred for medical evaluation within days to a couple of weeks, sooner if B symptoms are present.

Immunodeficiency and autoimmune disease

Immunodeficiency is most often secondary: HIV infection, long term glucocorticoids, chemotherapy, biologic drugs (TNF inhibitors), transplant medication, poorly controlled diabetes, malnutrition, chronic kidney disease, splenectomy and advanced age. In HIV, a CD4 count below 200 cells per µL (or an AIDS defining illness) defines AIDS; opportunistic infections and lymphoma follow. For the chiropractor the key point is that an immunosuppressed patient with new spinal pain has a much higher risk of vertebral osteomyelitis, discitis and epidural abscess, often with little or no fever, and a lower threshold for imaging and referral.

Autoimmune diseases share fatigue, low grade fever, arthralgia, raised ESR and CRP, and specific autoantibodies.

Section 3Gastrointestinal and genitourinary disorders

Visceral pain and referral to the back

Visceral afferents travel with sympathetic nerves into the same spinal segments that supply skin and muscle, so pain from an organ is felt in the dermatomes and myotomes of its segmental supply (convergence projection). Visceral pain is deep, diffuse and poorly localized, and is often accompanied by nausea, sweating or pallor. Its defining feature for the chiropractor is that it is not changed by spinal movement, posture or palpation, but it does change with organ function: eating, swallowing, bowel movements, urination, menstruation or exertion. Pain that wakes the patient, constant pain unrelieved by any position, and pain with fever, weight loss, jaundice, blood in urine or stool, or changes in bowel and bladder habit point to a visceral source (Figure 3.3).

Upper gastrointestinal tract

Gastroesophageal reflux disease causes heartburn and regurgitation after meals, on bending and lying flat, and may cause chronic cough, hoarseness or noncardiac chest pain. Alarm features that require endoscopy referral are dysphagia, odynophagia, weight loss, GI bleeding or anemia, persistent vomiting and new symptoms after about age 60. Long standing reflux can cause Barrett esophagus (columnar metaplasia), the precursor of esophageal adenocarcinoma.

Peptic ulcer disease is caused mainly by Helicobacter pylori and NSAIDs. Duodenal ulcer pain classically improves with food and returns two to three hours later or at night; gastric ulcer pain is worse with eating and causes weight loss. A posterior duodenal ulcer can penetrate the pancreas and present as mid back pain. Complications are bleeding (hematemesis, coffee ground vomitus, black tarry melena), perforation (sudden severe epigastric pain, board like abdomen, free air under the diaphragm on an upright chest film) and gastric outlet obstruction.

Gallstone disease favors women, obesity, age over 40, pregnancy and rapid weight loss. Biliary colic is steady right upper quadrant or epigastric pain after a fatty meal, lasting under about six hours and referring to the inferior angle of the right scapula. Acute cholecystitis adds fever, persistent pain and a positive Murphy sign (the patient stops inspiring when the examiner presses under the right costal margin). A stone in the common bile duct causes jaundice; ascending cholangitis causes the Charcot triad of fever, right upper quadrant pain and jaundice, and adding hypotension and confusion gives the Reynolds pentad. Ultrasound is the first imaging test.

Acute pancreatitis is caused mostly by gallstones and alcohol, also by very high triglycerides, hypercalcemia and certain drugs. Severe epigastric pain bores through to the back, is eased by sitting up and leaning forward, and comes with nausea and vomiting. Lipase over three times normal confirms it. Flank ecchymosis (Grey Turner sign) and periumbilical ecchymosis (Cullen sign) mark hemorrhagic disease. Pancreatic cancer causes dull epigastric and mid back pain, weight loss, new onset diabetes and painless jaundice with a palpable nontender gallbladder (Courvoisier sign) when it arises in the head.

Lower gastrointestinal tract and liver

Appendicitis begins as vague periumbilical pain (visceral, T10) with anorexia and nausea, then shifts to the right lower quadrant as the parietal peritoneum becomes inflamed, with maximal tenderness at McBurney point (one third of the way from the ASIS to the umbilicus). Supporting signs are rebound tenderness, Rovsing sign (pressing the left lower quadrant hurts the right), the psoas sign (pain on passive hip extension or resisted hip flexion, a retrocecal appendix irritating the right psoas) and the obturator sign (pain on internal rotation of the flexed right hip, a pelvic appendix). A positive psoas sign can mimic a lumbar or hip problem. Suspected appendicitis is an emergency referral. Diverticulitis is the older adult's equivalent on the left: left lower quadrant pain, fever and change in bowel habit.

Both forms of inflammatory bowel disease cause enteropathic arthritis: a peripheral arthritis that tracks bowel activity, and an axial spondyloarthritis (sacroiliitis, spondylitis) that is linked to HLA B27 and runs independently of the bowel. Young adults with inflammatory back pain plus chronic diarrhea, weight loss or blood in the stool need gastroenterology referral. Irritable bowel syndrome, in contrast, is recurrent abdominal pain related to defecation with altered stool form or frequency and no alarm features (no bleeding, anemia, weight loss, nocturnal symptoms or onset after 50).

Viral hepatitis causes malaise, anorexia, right upper quadrant discomfort, jaundice, dark urine and pale stools, with transaminases (ALT more than AST) in the hundreds or thousands. Hepatitis A and E spread by the fecal oral route and do not become chronic (E is dangerous in pregnancy). Hepatitis B spreads by blood, sex and birth; HBsAg means current infection, anti HBs means immunity (vaccination or recovery), and IgM anti HBc marks acute infection. Hepatitis C spreads mainly by blood (injection drug use), becomes chronic in most patients and is now curable with antivirals. Chronic hepatitis and alcohol lead to cirrhosis: spider angiomas, palmar erythema, gynecomastia, ascites, caput medusae, asterixis and an AST to ALT ratio over 2 in alcoholic disease.

Kidney, urinary tract and prostate

Nephrolithiasis: most stones are calcium oxalate and radiopaque; struvite (magnesium ammonium phosphate) stones form staghorn calculi with urease producing organisms such as Proteus; uric acid stones are radiolucent on plain film. Renal colic is severe, colicky flank pain radiating to the groin, testicle or labia, with nausea and hematuria. The patient writhes and cannot find a comfortable position, unlike the patient with mechanical back pain who lies still. Noncontrast CT is the standard test; stones under about 5 mm usually pass. An obstructed, infected kidney (fever plus a stone) is an emergency.

Lower urinary tract infection (cystitis) causes dysuria, frequency, urgency and suprapubic pain without fever; E. coli is the usual organism. Pyelonephritis adds fever, chills, flank pain, costovertebral angle tenderness (pain when the examiner strikes the angle between the 12th rib and the spine, sometimes called the Murphy punch test) and white cell casts in the urine; it needs same day medical care, and emergency care if the patient is septic, vomiting or pregnant.

Acute kidney injury is classified as prerenal (low perfusion, BUN to creatinine ratio over 20), intrinsic (acute tubular necrosis, glomerulonephritis, drugs) and postrenal (obstruction, often prostatic). Chronic kidney disease is a GFR under 60 mL/min/1.73 m² or kidney damage for three months or more, caused mainly by diabetes and hypertension. It brings anemia (low erythropoietin), hypertension, edema, metabolic acidosis, hyperkalemia and renal osteodystrophy (secondary hyperparathyroidism, osteomalacia, the "rugger jersey" spine of banded endplate sclerosis). NSAIDs should be avoided.

Benign prostatic hyperplasia arises in the transition zone and causes lower urinary tract symptoms: hesitancy, weak stream, dribbling, frequency, nocturia and incomplete emptying, sometimes acute retention. Prostate cancer arises mostly in the peripheral zone, felt as a hard, irregular nodule on digital rectal exam, and is often asymptomatic until it spreads. It metastasizes to the lumbar spine, pelvis and proximal femurs through the valveless vertebral venous system (Batson plexus), producing osteoblastic (sclerotic) lesions, including the "ivory vertebra." Back pain in an older man with urinary symptoms, weight loss or a known raised PSA is referred promptly.

Section 4Endocrine, metabolic and nutritional disorders

Diabetes mellitus

Type 1 diabetes is autoimmune destruction of beta cells, usually in youth, and presents with polyuria, polydipsia, weight loss and sometimes diabetic ketoacidosis (Kussmaul breathing, fruity breath, abdominal pain, dehydration). Type 2 diabetes is insulin resistance with relative insulin deficiency, linked to obesity and inactivity, and is often found on screening. Diagnosis requires a fasting glucose of 126 mg/dL or more, an HbA1c of 6.5 percent or more, a 2 hour oral glucose tolerance value of 200 mg/dL or more, or a random glucose of 200 or more with classic symptoms. Prediabetes is a fasting glucose of 100 to 125 or an HbA1c of 5.7 to 6.4 percent. Complications are microvascular (retinopathy, nephropathy, stocking and glove peripheral neuropathy) and macrovascular (coronary, cerebral and peripheral arterial disease). Musculoskeletal associations include adhesive capsulitis, carpal tunnel syndrome, Dupuytren contracture, DISH, Charcot (neuropathic) joints of the foot and diabetic amyotrophy (painful proximal thigh weakness). Hypoglycemia in the office (sweating, tremor, palpitations, hunger, confusion) in a patient on insulin or a sulfonylurea is treated with about 15 g of fast sugar if the patient can swallow, and with emergency services if not.

Thyroid, parathyroid and adrenal disorders

Osteoporosis, obesity and metabolic syndrome

Osteoporosis is low bone mass with microarchitectural deterioration and fragility fractures. On DEXA, a T score of minus 2.5 or lower (compared with a young adult reference) is osteoporosis; minus 1.0 to minus 2.5 is osteopenia (low bone mass). The Z score (compared with age matched peers) is used for premenopausal women, men under 50 and children; a low Z score prompts a search for secondary causes. A fragility fracture of the spine or hip establishes the diagnosis regardless of T score. Risk factors are female sex, older age, white or Asian ancestry, low body weight, early menopause, smoking, excess alcohol, inactivity, a parental hip fracture, long term glucocorticoids, hyperthyroidism, hyperparathyroidism, malabsorption and rheumatoid arthritis. FRAX estimates ten year fracture risk. Women 65 and older are screened. Vertebral compression fractures are the most common osteoporotic fracture and cause thoracic kyphosis and height loss; sudden thoracolumbar pain after a minor strain in an older woman is a fracture until proven otherwise. Thrust force is reduced or replaced by low force methods in osteoporotic patients. Osteomalacia (defective mineralization from vitamin D deficiency) differs by causing diffuse bone pain, proximal weakness, low or normal calcium and phosphate, high alkaline phosphatase and Looser zones (pseudofractures).

Body mass index of 25 to 29.9 is overweight and 30 or more is obesity. Metabolic syndrome is diagnosed when three of five criteria are met: waist over 40 inches (102 cm) in men or 35 inches (88 cm) in women; triglycerides 150 mg/dL or more; HDL under 40 in men or under 50 in women; blood pressure 130/85 or higher; fasting glucose 100 or higher.

Vitamin deficiencies

Section 5Infectious disease and the red flag approach

Infections a chiropractor must recognize

Fever, fever of unknown origin and sepsis

A fever is generally a temperature of 38.0°C (100.4°F) or higher. Normal adult vital signs are a heart rate of 60 to 100, respiratory rate of 12 to 20, and oxygen saturation of 95 percent or more. Fever of unknown origin is, in the classic definition, a temperature of 38.3°C (101°F) or higher on several occasions over more than three weeks that remains undiagnosed after a reasonable workup. Its causes fall into infection (endocarditis, tuberculosis, abscess, osteomyelitis), malignancy (lymphoma, leukemia, renal cell carcinoma), noninfectious inflammatory disease (giant cell arteritis, adult Still disease, lupus) and miscellaneous causes (drug fever, thromboembolism). FUO is always a medical referral.

Sepsis is life threatening organ dysfunction caused by a dysregulated response to infection. At the bedside, the quick SOFA score flags risk when two of three are present: respiratory rate of 22 or more, altered mentation, and systolic pressure of 100 mmHg or less. The older SIRS criteria are temperature over 38°C or under 36°C, heart rate over 90, respiratory rate over 20 and white cell count over 12,000 or under 4,000. An infected patient who is confused, breathing fast, hypotensive, mottled or not passing urine is septic until proven otherwise and needs emergency services; elderly and immunosuppressed patients may be hypothermic rather than febrile.

Red flags and urgency of referral

Individually most have modest accuracy; their value lies in clusters and in the clinician's willingness to act on them.

Co-management means that the chiropractor and the medical provider share care, each within scope, with clear communication. A good referral letter states the patient's identifying data, the reason for referral, the relevant history, exam and imaging findings, your working impression, the specific question you want answered, and whether you plan to continue care. Document the referral, the patient's response (including refusal, with the risks explained) and the follow up. In an emergency, phone first and send the paperwork afterwards; never let a patient with suspected MI, stroke or dissection drive themselves.

Words worth knowing

History, Posture, Gait and Orthopedic Tests of the Spine and Pelvis

The neuromusculoskeletal examination is the core of chiropractic diagnosis, and Part II gives it the largest share of the test plan. A well taken history usually tells you what is wrong before you touch the patient; posture, gait and a short list of well chosen orthopedic tests then confirm the tissue, the level and, just as importantly, whether the patient belongs in your office at all. This chapter covers the case history, posture and gait analysis, and the orthopedic tests of the cervical, thoracic and lumbopelvic regions, with exactly how each is done, what counts as positive and what a positive result suggests.

Section 1The neuromusculoskeletal case history

Structure of the history

The history moves from the chief complaint (in the patient's words) to the history of present illness, then past medical history (prior episodes, surgeries, fractures, cancer, systemic disease), medications (anticoagulants, steroids, NSAIDs, statins, fluoroquinolones), family history (inflammatory arthritis, cancer, aneurysm), social history (occupation, activity, smoking, alcohol, drugs, stress, sleep) and a review of systems, which is where visceral and systemic disease is uncovered. The present illness is organized with a mnemonic such as OPQRST:

Mechanism of injury

The mechanism predicts the injured tissue. Combined flexion with rotation under load (lifting and twisting) stresses the posterolateral annulus and produces disc injury. Axial loading (diving, a fall onto the feet or buttocks) causes compression or burst fractures, typically at the thoracolumbar junction, and calcaneal fractures from a fall onto the feet travel with lumbar fractures. Hyperextension stresses the facet joints, pars interarticularis (spondylolysis in gymnasts and linemen) and anterior longitudinal ligament. A fall on an outstretched hand injures the wrist, elbow and shoulder. Rapid acceleration and deceleration in a motor vehicle collision causes whiplash associated disorders (WAD); important details are the direction of impact, head position (rotated heads fare worse), headrest height, seat belt use, awareness of impact and immediate versus delayed symptoms.

Pain patterns

Distinguishing pain types is the central skill of the spinal history, because each points to a different tissue and a different management path.

• Local somatic pain arises from the injured structure itself (facet capsule, disc annulus, ligament, muscle, sacroiliac joint). It is aching and fairly well localized.
• Somatic referred pain is felt at a distance from a somatic source in the same segmental supply. It is deep, dull, diffuse, hard to localize, and usually stays above the knee (or elbow). Facet, disc and sacroiliac joints all produce it. There are no neurological deficits.
• Radicular pain results from an inflamed or compressed nerve root. It is sharp, shooting, lancinating or electric, travels in a narrow band, often goes below the knee into the foot (or below the elbow into the hand), and is worse in the limb than in the back. It is often aggravated by coughing, sneezing and nerve tension tests.
• Radiculopathy is objective loss of root function: dermatomal sensory loss, myotomal weakness and a reduced reflex. Radicular pain and radiculopathy often coexist but either may occur alone.
• Myelopathy is cord compression: clumsy hands, gait disturbance, bilateral paresthesia, bowel or bladder change, and upper motor neuron signs (hyperreflexia, Hoffmann, Babinski, clonus).
• Visceral referred pain (Chapter 3) is unaffected by movement and linked to organ function.
• Nociplastic pain (central sensitization) is widespread, disproportionate pain with allodynia and hyperalgesia, typical of fibromyalgia and some chronic spinal pain.

Mechanical versus nonmechanical pain

Mechanical pain varies with posture, movement and load, is eased by certain positions or rest, and has a pattern you can reproduce on examination. Morning stiffness lasts less than about 30 minutes. Nonmechanical pain is constant, unrelieved by rest or position, often worse at night, and suggests tumor, infection, inflammatory disease or a visceral source. Inflammatory back pain, typical of axial spondyloarthritis, has its own profile: onset before age 40, insidious onset, improvement with exercise, no improvement with rest, and night pain that improves on getting up (four of these five features support the diagnosis), plus prolonged morning stiffness and alternating buttock pain.

Red flags and yellow flags

Red flags (Chapter 3) point to serious pathology: a history of cancer, unexplained weight loss, fever, immunosuppression, injection drug use, significant trauma or osteoporosis, saddle anesthesia, bladder or bowel dysfunction, progressive neurological deficit and constant night pain. Yellow flags are psychosocial factors that predict persistent pain and disability: fear avoidance beliefs (the belief that movement causes harm), catastrophizing, depression and anxiety, passive coping, expectation that only passive treatment will help, job dissatisfaction, and compensation or litigation issues. Related terms are blue flags (the worker's perception that work is harmful or unsupportive), black flags (system and contextual obstacles such as compensation rules) and orange flags (psychiatric disorder needing specialist care). The STarT Back screening tool stratifies low back pain patients into low, medium and high risk of poor outcome so that care can be matched to risk.

Outcome measures

Validated outcome measures document the baseline, track progress, justify continued care and guide discharge. Change is judged against the minimal clinically important difference (MCID), the smallest change a patient perceives as meaningful.

Section 2Posture and gait assessment

Plumb line analysis

Static posture is viewed from the side, front and back with the patient standing relaxed, barefoot, feet a comfortable distance apart, against a plumb line (a weighted string that hangs truly vertical). In the lateral view the line is aligned just anterior to the lateral malleolus, and in ideal alignment it then passes through the landmarks shown in Figure 4.2. Deviations are described by the direction the body segment lies relative to the line: a forward head, for example, places the ear anterior to the line.

In the posterior view, the line falls from the external occipital protuberance through the spinous processes and gluteal cleft and midway between the knees and the medial malleoli. Look for head tilt, unequal shoulder and scapular heights, a lateral curve, uneven waist angles (the space between the arm and trunk), unequal iliac crest, PSIS and gluteal fold heights, genu valgum or varum, and calcaneal eversion. In the anterior view, note facial and clavicular symmetry, the chest, patellar orientation (squinting patellae suggest femoral anteversion) and foot arches.

Scoliosis screening and the Adams test

Scoliosis is a lateral curvature of the spine of 10 degrees or more (Cobb method), always accompanied by vertebral rotation when structural. Adolescent idiopathic scoliosis is the most common form; small curves are equally common in boys and girls, but curves that progress are far more common in girls, and the typical pattern is a right thoracic curve. Screening signs are unequal shoulder heights, a prominent scapula, asymmetric waist angles, a trunk shifted off the pelvis (a plumb line from C7 that misses the gluteal cleft) and a rib or lumbar prominence.

In the Adams forward bend test, the standing patient bends forward from the waist with knees straight, feet together and arms hanging, palms together. The examiner looks along the back from behind (and from the front) at eye level. A rib hump (thoracic) or paravertebral prominence (lumbar) on one side is positive and indicates vertebral rotation, meaning a structural curve; the rib hump lies on the convex side of the curve. A curve that is present standing but disappears on forward bending is functional (nonstructural), caused by a leg length difference, muscle spasm, pain or habitual posture. A scoliometer measures the angle of trunk rotation; 5 to 7 degrees is the usual threshold for radiographic referral. Skeletal maturity is graded by the Risser sign (ossification of the iliac apophysis, 0 to 5); risk of progression is highest in an immature patient (Risser 0 to 1) with a larger curve.

Leg length assessment

An anatomical (structural) leg length inequality is a true difference in bone length of the femur or tibia. A functional (apparent) inequality is created by pelvic obliquity, sacroiliac dysfunction, muscle imbalance, hip contracture or foot pronation, with bones of equal length.

The most accurate measure of anatomical inequality is an upright weight bearing radiograph of the pelvis and femoral heads with the patient standing evenly, or a scanogram. Differences under about 5 mm are common and of uncertain significance.

The gait cycle

One gait cycle runs from initial contact of one foot to the next initial contact of the same foot. At normal speed, stance phase takes about 60 percent and swing phase about 40 percent. There are two periods of double support (about 10 percent each); as speed increases double support shrinks, and running replaces it with a float (flight) phase. Stance is divided into initial contact (heel strike), loading response (foot flat), midstance, terminal stance (heel off) and preswing (toe off). Swing is divided into initial swing (acceleration), midswing and terminal swing (deceleration). Normal cadence is roughly 100 to 120 steps per minute, the step width a few centimeters, and the pelvis rotates and drops slightly to minimize vertical displacement of the center of mass.

Section 3Orthopedic examination of the cervical spine

Before you test: trauma screening and observation

After trauma, decide whether the neck needs imaging before it is moved. The Canadian C spine rule (for alert, stable adults) first asks about high risk factors: age 65 or older, a dangerous mechanism (fall from 1 m or five stairs, axial load to the head, high speed or rollover collision, ejection, bicycle collision) or paresthesias in the extremities. Any one means radiography (or CT). If none is present, low risk factors (simple rear end collision, sitting in the emergency department, ambulatory at any time, delayed onset of neck pain, no midline tenderness) allow safe assessment of motion; if the patient can actively rotate 45 degrees left and right, no imaging is needed. The NEXUS criteria clear the neck clinically when there is no posterior midline tenderness, no intoxication, normal alertness, no focal neurological deficit and no painful distracting injury.

Observe head carriage, guarding, torticollis and skin; palpate bony landmarks (C2 spinous is the first palpable midline bump below the occiput, C7 the most prominent, and C6 moves anteriorly under the finger on extension while C7 does not), facets, muscles, the supraclavicular fossa (cervical rib, nodes) and the carotid pulses.

Range of motion

Active motion is tested first, then passive, then resisted. In the Cyriax approach, pain on active and passive motion in the same direction implicates inert tissue (joint, capsule, ligament), while pain on resisted isometric contraction implicates contractile tissue (muscle, tendon). The O'Donoghue maneuver applies this directly: pain on resisted motion suggests strain, and pain on passive motion suggests sprain.

In the lower cervical spine, lateral flexion and rotation are coupled to the same side because of the 45 degree orientation of the facet joints. Loss of rotation to one side of more than about 10 degrees is an objective, trackable finding; the cervical flexion rotation test (rotation measured in full flexion, which isolates C1 to C2) is restricted in cervicogenic headache.

Foraminal and nerve root tests

The cervical intervertebral foramen narrows with extension, ipsilateral lateral flexion and ipsilateral rotation and opens with flexion, contralateral bending and traction. Compression tests therefore reproduce radicular symptoms when a root is already crowded by a disc herniation or uncovertebral and facet osteophytes, and distraction relieves them (Figure 4.3).

No single cervical test is decisive. A clinical prediction cluster for cervical radiculopathy combines a positive ULTT 1, ipsilateral rotation under 60 degrees, relief with distraction and a positive Spurling: three of four positive makes radiculopathy likely, and all four makes it very likely. Confirm with the neurological exam (dermatomes, myotomes and reflexes, covered in Chapter 6) and look for upper motor neuron signs (Hoffmann, Babinski, hyperreflexia, gait change) that turn a radicular picture into myelopathy.

Vertebral artery and cervical artery screening

Traditional premanipulative screening tests place the neck in sustained rotation and extension to stretch the vertebral artery, watching for dizziness, nystagmus, visual disturbance, nausea or other brainstem signs.

The evidence is clear that these provocative tests have poor sensitivity and cannot predict which patients will suffer a cervical artery dissection or stroke. A negative test does not clear a patient for manipulation. Current consensus emphasizes the history: recognizing the patient who may already have a dissection in progress. Vertebral artery dissection classically produces sudden, unusual occipital or upper neck pain and headache, followed by brainstem signs (the 5 Ds and 3 Ns: dizziness, diplopia, dysarthria, dysphagia, drop attacks, nausea, nystagmus, numbness, plus ataxia). Internal carotid dissection produces anterolateral neck, face or eye pain with an ipsilateral Horner syndrome, pulsatile tinnitus or a transient ischemic attack. A positive screening test or such a history means no cervical manipulation and immediate referral.

Section 4Orthopedic examination of the thoracic spine and ribs

Inspection, motion and the ribs

The thoracic spine is the stiffest spinal region because the ribs, sternum and nearly coronal facets limit flexion and extension, while rotation is relatively free. Commonly taught thoracic ranges are about 20 to 45 degrees of flexion, 25 to 45 degrees of extension, 20 to 40 degrees of lateral flexion and 35 to 50 degrees of rotation, usually measured with the lumbar spine included as thoracolumbar motion. Inspect for kyphosis (a smooth round back, a sharp angular gibbus from a collapsed vertebra, or the wedged vertebrae of Scheuermann disease), scoliosis (Adams test, Section 2), scapular position and chest shape (pectus excavatum, pectus carinatum, barrel chest).

The upper ribs move in a pump handle fashion (increasing the anteroposterior diameter), the lower ribs in a bucket handle fashion (increasing the transverse diameter), and ribs 11 and 12 in a caliper motion. Thoracic pain must always be weighed against visceral sources: heart, aorta, esophagus, lungs and pleura, gallbladder, pancreas and kidney (Chapter 3), as well as herpes zoster before the rash appears.

Thoracic and rib tests

The direction of umbilical movement in Beevor sign follows the stronger muscle: with weak lower abdominals the intact upper fibers pull the umbilicus toward the head. Abdominal superficial reflexes (T8 to T12) complement it, and their asymmetric loss in a child with scoliosis suggests a syrinx.

Thoracic outlet syndrome

The thoracic outlet is the passage from the root of the neck to the axilla through which the brachial plexus, subclavian artery and subclavian vein travel. There are three sites of potential compression (Figure 4.4): the interscalene triangle (anterior scalene in front, middle scalene behind, first rib below; the plexus and artery pass through it, the vein passes in front of the anterior scalene), the costoclavicular space (between the clavicle and first rib) and the subcoracoid (pectoralis minor) space beneath the pectoralis minor tendon at the coracoid. Contributing factors include a cervical rib or long C7 transverse process, scalene hypertrophy or fibrous bands, a healed clavicle fracture, drooping shoulders and repetitive overhead work.

More than 90 percent of cases are neurogenic, usually affecting the lower trunk (C8 and T1): aching in the neck, shoulder and medial arm, paresthesia in the ulnar forearm and fourth and fifth fingers, worse with overhead activity and carrying, and, in long standing cases, wasting of the thenar eminence (Gilliatt Sumner hand). Arterial TOS causes coldness, pallor, claudication of the arm and emboli; venous TOS causes swelling, cyanosis and heaviness, and effort thrombosis of the subclavian vein (Paget Schroetter syndrome) after vigorous arm use is an urgent referral.

Pulse obliteration during these positions also occurs in many people without symptoms, so a pulse change alone has poor specificity. The meaningful finding is reproduction of the patient's own symptoms, ideally on more than one test, combined with a compatible history and a neurological exam that excludes C8 radiculopathy and ulnar neuropathy at the elbow. A chest or cervical film may show a cervical rib or apical lung lesion; a Pancoast tumor of the lung apex can mimic TOS with shoulder and ulnar arm pain plus Horner syndrome.

Section 5Orthopedic examination of the lumbar spine and pelvis

Lumbar motion

Commonly taught lumbar ranges are about 40 to 60 degrees of flexion, 20 to 35 degrees of extension, 15 to 25 degrees of lateral flexion and only 3 to 18 degrees of rotation, because the sagittally oriented facets block twisting. Watch the quality of motion: a painful arc, deviation to one side during flexion (a lateral shift away from a posterolateral disc protrusion), reversal of lumbopelvic rhythm when returning from flexion, and a flat segment that does not open on flexion. The modified Schöber test marks the lumbosacral junction (the level of the dimples of Venus) and points 10 cm above and 5 cm below; the 15 cm span should lengthen by at least about 5 cm on full flexion, and less than that supports ankylosing spondylitis or other causes of restricted lumbar flexion.

Nerve tension tests

Straight leg raising pulls the sciatic nerve and the L4 to S1 roots caudally through their foramina. The first 30 degrees or so takes up slack with little root movement; between about 30 and 70 degrees the roots move and are placed under tension; beyond 70 degrees most of the strain falls on the lumbar joints, the sacroiliac joint and the hamstrings (Figure 4.5).

Pressure, facet and space occupying lesion tests

Sacroiliac, hip and soft tissue tests

Single sacroiliac tests are unreliable. The best supported approach is a cluster of provocation tests: distraction (gapping of the anterior joint by pressing the ASISs apart), compression (side lying downward pressure on the iliac crest), thigh thrust (posterior shear through the femur with the hip flexed 90 degrees), sacral thrust (prone, pressure on the sacrum) and Gaenslen. Three or more positive tests out of five, together with pain below L5 and no centralization during repeated movements, make the sacroiliac joint a likely pain source.

Nonorganic signs: Hoover and Waddell

Some findings indicate that pain behavior is not explained by structural disease alone. They must be interpreted carefully: they identify illness behavior and psychosocial distress that need to be addressed, not proof that the patient is lying, and they can coexist with genuine pathology.

Three or more of the five Waddell categories is considered significant. A positive score predicts poorer outcomes and calls for attention to yellow flags and, often, a multidisciplinary approach; it does not by itself justify ending care or a conclusion of malingering.

Words worth knowing

Orthopedic Examination of the Extremities and Musculoskeletal Diagnosis

Most patients with a sore shoulder, a numb hand, a twisted knee or a painful heel can be diagnosed with a careful history, range of motion and the right three or four orthopedic tests. The board rewards the same skill: knowing how each test is done, what a positive looks like and which structure it implicates. This chapter works joint by joint through the extremities, then turns to the patterns that separate sprain from fracture, osteoarthritis from inflammatory arthritis, and a trigger point from fibromyalgia.

Section 1The shoulder

Functional anatomy that drives the tests

The shoulder complex has four articulations: glenohumeral (GH), acromioclavicular (AC), sternoclavicular (SC) and scapulothoracic. The shallow glenoid, deepened by the labrum, relies on the rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) to hold the head centered while the deltoid elevates. The supraspinatus tendon and subacromial bursa pass beneath the coracoacromial arch with every elevation, which is why impingement is the commonest cause of shoulder pain.

Normal active motion is about flexion 180°, extension 50 to 60°, abduction 180°, internal rotation 70 to 90° and external rotation 90°. Scapulohumeral rhythm is about 2 to 1 (120° GH and 60° scapular in full abduction), and the humerus must externally rotate to clear the greater tuberosity overhead.

Always compare active with passive range and add resisted isometric testing. Painful active motion with full painless passive motion and painful resisted movement points to a contractile lesion (muscle or tendon). Loss of both active and passive motion in the capsular pattern (for the GH joint, external rotation most limited, then abduction, then internal rotation) points to the capsule, classically adhesive capsulitis or advanced glenohumeral arthritis. Weakness with full passive range suggests a tear or a nerve lesion.

Impingement

Subacromial impingement is compression of the supraspinatus tendon, the long head of biceps and the subacromial bursa beneath the coracoacromial arch. Contributors include a hooked (type III) acromion, AC osteophytes, weak scapular stabilizers and thoracic kyphosis. Neer described three stages: stage I edema and hemorrhage (typically under age 25, reversible), stage II fibrosis and tendinitis (25 to 40) and stage III bone spurs and tendon rupture (over 40).

Rotator cuff tests

Each cuff muscle has a test that isolates it. The supraspinatus (suprascapular nerve, C5 and C6) initiates abduction and is the tendon torn most often, usually near its insertion on the greater tuberosity in the hypovascular critical zone. Infraspinatus (suprascapular nerve) and teres minor (axillary nerve) externally rotate. Subscapularis (upper and lower subscapular nerves) internally rotates. Calcific tendinitis also favors the supraspinatus.

Instability, biceps and labrum

About 95 percent of GH dislocations are anterior (abduction, external rotation and extension); the shoulder looks squared off and the axillary nerve is most often injured (check the lateral deltoid skin). A Hill Sachs lesion is a posterolateral humeral head impaction fracture and a Bankart lesion an anteroinferior labral avulsion. Posterior dislocation follows seizure or electrocution, with the arm locked in internal rotation and a lightbulb sign on AP.

The AC and SC joints

The AC joint is injured by a fall onto the point of the shoulder with the arm adducted. Tenderness sits directly over the joint, and the cross body adduction test (horizontal adduction of the 90° flexed arm across the chest) compresses it and reproduces pain. The AC shear test squeezes the clavicle and spine of the scapula together. The Rockwood classification grades separations:

The SC joint usually dislocates anteriorly (a visible bump, benign), but a posterior SC dislocation can compress the trachea, esophagus and great vessels: dyspnea, dysphagia or venous congestion of the arm is an emergency.

Adhesive capsulitis

Adhesive capsulitis (frozen shoulder) is fibrosis and contracture of the GH capsule, typically at age 40 to 60, more in women, and strongly associated with diabetes (often bilateral and stubborn), thyroid disease, immobilization and stroke. It passes through a painful freezing phase (to about 9 months), a frozen phase (about 4 to 12 months, stiffness more than pain) and a thawing phase (up to about 2 years). The hallmark is equal loss of active and passive motion in the capsular pattern, external rotation worst, with a firm end feel. Films are normal; arthrography shows a small capsule.

Section 2The elbow, wrist and hand

The elbow

The elbow is three joints in one capsule: the humeroulnar (hinge), the humeroradial and the proximal radioulnar (pivot). Normal motion is about 0° extension to 140 to 150° flexion and 80 to 90° each of supination and pronation. The carrying angle, the valgus angle between arm and forearm in full extension, is about 5 to 15° and greater in women. A cubitus varus (gunstock) deformity is the classic late result of a malunited supracondylar fracture. The capsular pattern is flexion more limited than extension.

The lateral epicondyle is the common extensor origin (ECRB is the key tendon in lateral epicondylopathy) and the medial epicondyle the common flexor and pronator origin. The ulnar collateral ligament resists valgus and fails in throwers; the radial collateral complex resists varus. The ulnar nerve runs in the cubital tunnel behind the medial epicondyle.

Lateral epicondylopathy (tennis elbow) is degenerative tendinosis of the ECRB origin from repetitive gripping and wrist extension, peaking at 35 to 55 years; most patients do not play tennis. It must be distinguished from radial tunnel syndrome (tender 4 to 5 cm distal to the epicondyle) and C6 radiculopathy. Medial epicondylopathy (golfer's elbow) is less common and often accompanies ulnar neuritis.

Also know olecranon bursitis (aspirate a hot one to exclude infection or gout) and radial head subluxation (nursemaid's elbow) in a toddler pulled by the hand.

Peripheral nerves of the forearm and hand

Nerve entrapments in the upper limb are high yield because they mimic cervical radiculopathy. The key is that a peripheral nerve lesion follows the nerve's cutaneous field and its muscles, while a root lesion follows a dermatome and myotome and often has neck signs and reflex change.

Carpal tunnel syndrome, the commonest entrapment neuropathy, causes numbness of the lateral three and a half digits that is worse at night and eased by shaking the hand, then thenar atrophy with weak abductor pollicis brevis. Thenar skin is spared because the palmar cutaneous branch passes superficial to the ligament; thenar numbness suggests a proximal lesion. Risk factors are pregnancy, hypothyroidism, diabetes, rheumatoid arthritis, acromegaly and repetitive use; nerve conduction studies confirm it. In a double crush, a proximal (root) compression makes the nerve more vulnerable distally.

The ulnar nerve is compressed at the cubital tunnel (most common) or Guyon canal (cyclists). A Guyon canal lesion spares dorsal ulnar hand sensation, because the dorsal cutaneous branch leaves above the wrist. Advanced palsy produces the ulnar claw. The radial nerve is compressed in the spiral groove (Saturday night palsy, wrist drop with triceps spared) or as the posterior interosseous nerve (finger drop, no sensory loss).

Wrist and hand conditions

Normal wrist motion is about 80° flexion, 70° extension, 20° radial deviation and 30° ulnar deviation. A fall on the outstretched hand (FOOSH) produces a predictable set of injuries by age: distal radius fracture in older adults, scaphoid fracture in young adults, and buckle (torus) or supracondylar fracture in children.

• Scaphoid fracture is the most commonly fractured carpal bone. Look for tenderness in the anatomic snuffbox and over the scaphoid tubercle and pain with axial thumb compression. Initial films may be normal; immobilize in a thumb spica and repeat imaging in 10 to 14 days or obtain MRI. Because the blood supply enters distally and flows retrograde, waist and proximal pole fractures risk avascular necrosis and nonunion.
• Colles fracture: distal radius with dorsal angulation and displacement (dinner fork deformity). Smith fracture: volar displacement (reverse Colles). Barton fracture: intra-articular rim fracture with carpal subluxation. Boxer's fracture: neck of the fifth metacarpal. Bennett fracture: intra-articular base of the first metacarpal; Rolando is its comminuted form.
• Gamekeeper's (skier's) thumb is a tear of the ulnar collateral ligament of the thumb MCP joint; a Stener lesion (adductor aponeurosis trapped between the torn ends) prevents healing and needs surgery.
• Finger tendon injuries: mallet finger (avulsion of the terminal extensor, DIP droops), jersey finger (avulsion of FDP, usually the ring finger, cannot flex the DIP), boutonnière deformity (central slip rupture, PIP flexion with DIP hyperextension) and swan neck deformity (PIP hyperextension with DIP flexion), the last two classic in rheumatoid arthritis.

Dupuytren contracture is painless fibrosis of the palmar fascia, forming nodules and cords that pull the ring and little fingers into MCP and then PIP flexion. It favors men of northern European ancestry over 50 and is linked to diabetes, alcohol, smoking, epilepsy and family history. The tabletop (Hueston) test is positive when the palm cannot lie flat.

Trigger finger (stenosing tenosynovitis) is thickening of the flexor tendon sheath at the A1 pulley over the metacarpal head, so a nodule on the tendon catches as it passes. The finger clicks, locks in flexion and may need to be pulled straight. The ring finger and thumb are most often involved, and diabetes and rheumatoid arthritis are risk factors.

Section 3The hip and knee

The hip

The hip is a deep ball and socket joint reinforced by the iliofemoral, pubofemoral and ischiofemoral ligaments and a labrum. Normal motion is about flexion 120°, extension 10 to 30°, abduction 45°, adduction 30°, internal rotation 35 to 40° and external rotation 45°. Intra-articular disease shows first as loss of internal rotation (capsular pattern: flexion, abduction and internal rotation limited). Hip joint pain is felt in the groin and may refer to the knee. Lateral pain over the trochanter is usually greater trochanteric pain syndrome (gluteal tendinopathy with or without bursitis).

The Trendelenburg sign is easy to get backward: standing on the right leg, a weak right gluteus medius lets the left side of the pelvis drop. A Trendelenburg gait is the dynamic version, or the patient lurches the trunk over the weak stance hip (gluteus medius lurch).

Leg length is measured from the ASIS to the medial malleolus (true or anatomic length); a difference here is structural. Measuring from the umbilicus to the medial malleolus gives apparent length, which reflects pelvic obliquity or contracture. A difference in apparent length with equal true lengths is functional.

Hip conditions by age

The knee

The ACL runs from the anterior tibia to the lateral femoral condyle and resists anterior translation and internal rotation of the tibia; the PCL, the strongest, runs from the posterior tibia to the medial femoral condyle and resists posterior translation. The MCL resists valgus and is attached to the medial meniscus, which is C shaped, less mobile and torn more often; the LCL resists varus and runs to the fibular head. Motion is 0 to about 135° flexion; the capsular pattern is flexion more limited than extension.

A classic ACL injury is a noncontact cutting or deceleration injury with a pop and hemarthrosis within hours; women are at higher risk. The unhappy triad is ACL, MCL and medial meniscus from a valgus rotation blow. A Segond fracture (lateral tibial plateau avulsion) nearly proves an ACL tear. The PCL fails in a dashboard injury. Meniscal tears give joint line tenderness, delayed swelling, catching and locking; a knee locked short of extension (bucket handle tear) needs prompt referral. A tibiofemoral dislocation threatens the popliteal artery: check pulses.

Patellofemoral tests and the extensor mechanism

The Q angle (ASIS to mid patella to tibial tubercle) is about 13° in men and 18° in women; a larger angle increases lateral patellar pull, predisposing to patellofemoral pain syndrome (anterior knee pain with stairs, squatting and prolonged sitting) and lateral dislocation.

Extensor mechanism traction problems depend on age: Osgood Schlatter disease at the tibial tubercle in adolescents, Sinding Larsen Johansson at the inferior patellar pole, and patellar tendinopathy (jumper's knee) in adults. Bursitis is named by site: prepatellar (kneeling), infrapatellar and pes anserine (under sartorius, gracilis and semitendinosus). A ruptured Baker cyst (between medial gastrocnemius and semimembranosus) mimics deep vein thrombosis.

The Ottawa knee rules call for radiographs after acute knee injury if any one of these is present: age 55 or older, isolated tenderness of the patella, tenderness of the fibular head, inability to flex to 90°, or inability to bear weight for four steps both immediately and in the clinic.

Section 4The ankle and foot

Ankle anatomy and sprains

The talus is wider anteriorly, so the ankle is most stable in dorsiflexion and least stable in plantarflexion, which is why sprains happen with the foot pointed and turned in. Motion is about 20° dorsiflexion and 50° plantarflexion, with inversion and eversion mainly at the subtalar joint.

The lateral ligament complex comprises the anterior talofibular (ATFL), calcaneofibular (CFL) and posterior talofibular (PTFL) ligaments, and an inversion sprain tears them in that order, the ATFL first. The strong medial deltoid ligament resists eversion; medial tenderness after an eversion injury should prompt a search for a fibular fracture. External rotation injures the syndesmosis (high ankle sprain), which heals slowly.

Ankle sprains are graded like other sprains: grade I stretching of the ATFL with minimal swelling and no laxity, grade II partial tear of the ATFL with or without CFL involvement, moderate swelling, ecchymosis and mild laxity, and grade III complete rupture of the ATFL and CFL with marked swelling, inability to bear weight and gross instability. Most heal with functional rehabilitation rather than prolonged immobilization.

Achilles, heel and forefoot

Achilles tendon rupture classically strikes a middle aged recreational athlete at push off: a feeling of being kicked, a palpable gap 2 to 6 cm above the insertion, and weak (not absent) plantarflexion through the toe flexors and peroneals, which is why the Thompson test matters. Risk factors include fluoroquinolones, steroid injection and prior tendinopathy.

Plantar fasciopathy is the commonest adult heel pain: pain with the first morning steps that eases with walking, and tenderness at the medial calcaneal tubercle; heel spurs are incidental. Burning sole pain suggests tarsal tunnel syndrome, and posterior heel pain at age 8 to 14 is usually Sever disease.

Morton neuroma is perineural fibrosis of an interdigital nerve, usually in the third web space, causing burning and a pebble in the shoe feeling, worse in narrow shoes. At the first MTP joint, think of hallux valgus, hallux rigidus, turf toe and gout (podagra).

Fractures and the Ottawa ankle rules

The Ottawa ankle rules are nearly 100 percent sensitive for clinically important fractures. An ankle series is indicated for malleolar zone pain plus any one of: bone tenderness at the posterior edge or tip of the distal 6 cm of the lateral or medial malleolus, or inability to bear weight for four steps both immediately and at examination. A foot series is indicated for midfoot pain plus tenderness at the base of the fifth metatarsal or the navicular, or the same weight bearing failure. They do not apply to intoxicated patients, those with reduced sensation or multiple injuries.

Section 5Diagnosis of muscle, bone and joint conditions

Sprains, strains and how to grade them

A sprain is an injury to a ligament (or joint capsule); a strain is an injury to a muscle or tendon (the musculotendinous unit). The easiest way to separate them at the bedside is selective tension. Passive movement that stretches an inert structure hurts in a sprain. Resisted isometric contraction and passive stretch of the muscle hurt in a strain. Strains occur most often at the musculotendinous junction in muscles that cross two joints and contract eccentrically, such as the hamstrings, rectus femoris, gastrocnemius and adductors.

Healing passes through inflammatory, proliferative (type III collagen) and remodeling (aligned type I collagen) phases over months. End feel is part of grading: a normal ligament has a firm, abrupt end point; a soft or empty end feel suggests rupture, and an empty end feel with severe pain but no mechanical block raises concern for acute bursitis, abscess or tumor.

Tendinopathy and bursitis

Tendinopathy is the umbrella term for painful tendon disorders; most chronic cases are degenerative tendinosis (disorganized collagen, neovascularization, few inflammatory cells), so treatment centers on progressive loading. Tenosynovitis involves the sheath (de Quervain, trigger finger), and enthesitis, inflammation at a tendon insertion, marks the spondyloarthropathies.

A bursa is a synovial lined sac that reduces friction. Bursitis gives localized tenderness and swelling over the bursa, and pain with compression or with motion of the overlying tendon. Superficial bursae (olecranon, prepatellar) swell visibly; deep bursae (subacromial, trochanteric, iliopsoas) do not. Septic bursitis (usually S. aureus, through skin breaks) produces warmth, redness, cellulitis and sometimes fever; aspiration is diagnostic, and gout and rheumatoid arthritis can also inflame bursae.

Fractures by region and the red flags

Suspect a fracture with a significant mechanism, point bone tenderness, deformity, crepitus, inability to bear weight or use the limb, and pain with axial loading, percussion or tuning fork vibration over bone. Plain films in two orthogonal views (one view is no view), including the joints above and below for long bones, are the starting point. Some fractures are occult at first: scaphoid, femoral neck, stress fractures and nondisplaced fractures in osteoporotic bone may need repeat films, MRI or bone scan.

Growth plate injuries are graded by Salter Harris (SALTR): I through the physis (S, straight), II physis and metaphysis (A, above; most common), III physis and epiphysis (L, lower; intra-articular), IV through all three (T), V crush (R, rammed; worst prognosis).

The emergencies are open fractures, fractures with vascular compromise and compartment syndrome (after tibial or forearm fractures and crush injury). Its earliest, most reliable signs are pain out of proportion to the injury and pain on passive stretch of the compartment muscles; pallor, paresthesia, paralysis and pulselessness are late. Fasciotomy is urgent.

Arthritis: reading the pattern

Sort arthritis by number of joints, which joints and symmetry, inflammatory (stiffness over an hour, raised ESR and CRP) or mechanical (stiffness under 30 minutes) behavior, and extra-articular features. A hot, swollen single joint is septic arthritis until aspiration proves otherwise (S. aureus, or gonococcus in young sexually active adults); crystals are the other main cause.

Rheumatoid arthritis also causes nodules, lung disease and Felty syndrome. Hand deformities include ulnar deviation at the MCP joints, swan neck and boutonnière deformities. The cervical spine finding that matters to a chiropractor is atlantoaxial instability from erosion or laxity of the transverse ligament; an atlantodental interval over 3 mm in an adult is abnormal, and high velocity manipulation of the upper cervical spine is contraindicated in active RA.

The seronegative spondyloarthropathies share HLA B27, enthesitis, sacroiliitis, anterior uveitis and negative RF. Ankylosing spondylitis starts in young men with inflammatory back pain that improves with exercise, a reduced Schober test (under 5 cm increase over 10 cm) and chest expansion under 2.5 cm, and a rigid spine that fractures easily. Psoriatic arthritis favors DIP joints with dactylitis and nail pitting. Reactive arthritis follows Chlamydia or enteric infection with arthritis, urethritis and conjunctivitis. Enteropathic arthritis accompanies inflammatory bowel disease.

Myofascial pain, fibromyalgia and their mimics

Myofascial pain syndrome is regional pain from trigger points: hyperirritable spots in a taut band that refer pain in a set pattern. Active points reproduce the familiar pain; latent ones hurt only when pressed. Supporting signs are a local twitch response, a jump sign and weakness without atrophy. Classic referrals: upper trapezius to the temple, infraspinatus deep into the anterior shoulder, gluteus minimus down the lateral leg (mimicking L5 radiculopathy).

Fibromyalgia is chronic widespread pain with fatigue, unrefreshing sleep and cognitive symptoms, attributed to central sensitization; it is commoner in women, coexists with IBS, headache and mood disorders, and laboratory tests are normal. The 1990 ACR criteria required widespread pain for 3 months and 11 of 18 tender points. The 2010 and 2016 criteria use the widespread pain index (WPI) and symptom severity scale (SSS): WPI 7 or more with SSS 5 or more, or WPI 4 to 6 with SSS 9 or more, generalized pain in 4 of 5 regions, for at least 3 months. Graded aerobic exercise has the best evidence.

Screen for mimics. Polymyalgia rheumatica (over 50, shoulder and hip girdle stiffness, high ESR, dramatic steroid response) coexists with giant cell arteritis in 15 to 20 percent: ask about headache, jaw claudication and vision. Polymyositis causes proximal weakness with raised CK.

When to refer

Refer or image first for suspected fracture or dislocation, neurovascular compromise, a hot joint, fever, weight loss or cancer history, unremitting night pain, progressive neurologic deficit, compartment syndrome, a locked knee, a complete tendon rupture, a limping child with limited hip rotation, and signs of giant cell arteritis.

Words worth knowing

The Neurologic Examination and Neurologic Diagnosis

A neurologic exam answers two questions: is there a lesion, and where is it? Once you can place a lesion in the brain, brainstem, cord, root, plexus, peripheral nerve, junction or muscle, the differential shrinks to a handful of diagnoses, and the urgency becomes obvious. The board tests this localizing logic constantly, and in practice it is what separates the radiculopathy you can manage from the myelopathy, cauda equina syndrome or dissection you must refer today.

Section 1Cranial nerve and central nervous system examination

Mental status

Start with level of consciousness and orientation (person, place, time, situation), then attention (serial sevens, spelling WORLD backward), memory (three word recall at 5 minutes), language (naming, repetition, comprehension, reading, writing), visuospatial skill (clock drawing) and judgment. The Mini Mental State Examination scores 0 to 30, with 23 or below suggesting cognitive impairment; the Montreal Cognitive Assessment is more sensitive for mild impairment, with under 26 abnormal. In trauma or altered consciousness use the Glasgow Coma Scale: eyes 1 to 4, verbal 1 to 5, motor 1 to 6, total 3 to 15; 8 or less means coma and a threatened airway.

Two language deficits localize precisely. Broca (expressive) aphasia, from the inferior frontal gyrus of the dominant hemisphere, gives halting, effortful speech with good comprehension. Wernicke (receptive) aphasia, from the superior temporal gyrus, gives fluent but meaningless speech with poor comprehension. Both impair repetition; conduction aphasia (arcuate fasciculus) impairs repetition alone.

The twelve cranial nerves

Pupils, eyes and hearing

The pupillary light reflex uses CN II as the afferent limb and CN III (parasympathetic, via the Edinger Westphal nucleus) as the efferent limb; light in one eye constricts both pupils (direct and consensual). In the swinging flashlight test, a relative afferent pupillary defect (Marcus Gunn pupil) dilates paradoxically when the light swings to it, a sign of optic nerve disease such as optic neuritis. Horner syndrome, interruption of the oculosympathetic chain, gives ipsilateral ptosis, miosis and anhidrosis; causes include Pancoast tumor, carotid dissection and lateral medullary infarction. The Argyll Robertson pupil of neurosyphilis accommodates but does not react to light.

Extraocular movements are tested in an H pattern. Internuclear ophthalmoplegia from a lesion of the medial longitudinal fasciculus produces failure of adduction in the eye on the side of the lesion with nystagmus of the abducting eye; bilateral INO in a young adult strongly suggests multiple sclerosis.

Vertigo has a peripheral or central source. Benign paroxysmal positional vertigo causes brief spinning (under a minute) with head position change; the Dix Hallpike maneuver (head turned 45°, patient brought quickly supine with the head extended over the table edge) produces delayed, fatiguing, torsional upbeating nystagmus for the posterior canal, and the Epley maneuver treats it. Central vertigo from a cerebellar or brainstem stroke tends to have nonfatiguing, direction changing or vertical nystagmus, a normal head impulse test and other neurologic signs; this is a red flag.

Cerebellar examination

The cerebellum coordinates movement on the same side of the body, so a right hemisphere lesion causes right limb ataxia. The vermis controls the trunk and gait (truncal ataxia, wide based gait, typical of alcohol related degeneration); the hemispheres control the limbs. Signs are summarized by DANISH: dysdiadochokinesia, ataxia, nystagmus, intention tremor, slurred (scanning) speech and hypotonia.

Section 2Motor examination

Inspection and tone

Look first. Note posture, symmetry, atrophy (compare thenar eminences, first dorsal interossei, calves), fasciculations (spontaneous twitches of motor units, a lower motor neuron sign) and involuntary movements (resting tremor of Parkinson disease, chorea, myoclonus). Then assess tone, the resistance to passive movement of a relaxed limb.

The pronator drift test is a sensitive screen for subtle UMN weakness: arms held forward, palms up, eyes closed, for 20 to 30 seconds. The weak arm pronates and drifts downward.

Grading strength

Grade 3 is the pivotal grade: the limb can just overcome gravity. Test proximal and distal muscles, compare sides, and stabilize the proximal segment so that substitution does not hide weakness. Pain inhibition, poor effort and give way weakness (sudden collapse after initial full strength) are common causes of apparent weakness that are not neurologic.

Myotomes

A myotome is the group of muscles supplied mainly by one root. Most muscles receive two or three roots, so a single root lesion produces partial weakness, never paralysis; complete paralysis of a muscle points to a peripheral nerve.

Functional screens are fast: heel walking tests L4 and L5 dorsiflexors, toe walking tests S1 plantarflexors (ten single leg heel raises are needed to detect mild S1 weakness), and squatting and rising tests L3 and L4.

Upper versus lower motor neuron lesions

The upper motor neuron (UMN) runs from the motor cortex through the internal capsule, cerebral peduncle and pyramid, crosses at the pyramidal decussation in the lower medulla, and descends in the lateral corticospinal tract to synapse in the anterior horn. The lower motor neuron (LMN) runs from the anterior horn cell through the root, plexus and peripheral nerve to the muscle. Above the decussation a lesion produces contralateral signs; below it, ipsilateral signs.

Section 3Sensory examination

Two pathways, two sets of tests

Every bedside sensory test probes one of two ascending systems. The dorsal column medial lemniscus pathway carries fine touch, vibration, proprioception and two point discrimination. Its first order fibers enter the dorsal root and ascend ipsilaterally in the fasciculus gracilis (legs, medial) and fasciculus cuneatus (arms, lateral, present above T6), synapse in the nucleus gracilis and cuneatus of the medulla, cross as internal arcuate fibers, and ascend in the medial lemniscus to the ventral posterolateral (VPL) thalamus and postcentral gyrus. The anterolateral (spinothalamic) pathway carries pain, temperature and crude touch. Its fibers synapse in the dorsal horn, cross within one or two segments in the anterior white commissure and ascend contralaterally to the VPL thalamus.

Normal two point discrimination is about 2 to 5 mm at the fingertips, 8 to 15 mm on the palm and 40 mm or more on the back. Distal loss of vibration is often the earliest sign of a length dependent peripheral neuropathy, typically diabetic; the 10 g monofilament identifies a foot at risk of ulceration. Loss of stereognosis, graphesthesia or sensory extinction (a touch on one side is felt but missed when both sides are touched together) with intact primary sensation points to the contralateral parietal lobe.

Dermatomes and peripheral nerve fields

A dermatome is the skin area supplied by one spinal root. Adjacent dermatomes overlap, so a single root lesion causes a smaller and patchier deficit than the map suggests, and loss is usually greater for pain than for touch. A peripheral nerve field has sharper borders and usually combines fibers from several roots.