7.3 Musculoskeletal Assessment & Disorders

The Musculoskeletal Examination

The focused musculoskeletal exam follows inspection, palpation, and movement. Inspect for symmetry, deformity, swelling, erythema, muscle atrophy, and gait. Palpate for warmth, tenderness, crepitus (a grating sensation with joint movement), and effusion. Assess range of motion (ROM) actively first (patient moves the joint) and passively only if active motion is limited; never force a joint past resistance or pain.

Muscle strength grading is tested against resistance and graded on a 0 to 5 scale:

Grades 3, 4, and 5 are the most frequently tested: remember grade 3 as "against gravity only." Always compare sides and document by muscle group.

Osteoporosis

Osteoporosis is decreased bone density with microarchitectural deterioration, leading to fragility fractures of the hip, spine (compression fractures causing height loss and kyphosis — the "dowager's hump"), and wrist. Diagnosis is by dual-energy x-ray absorptiometry (DEXA): a T-score of -2.5 or lower defines osteoporosis, and -1.0 to -2.5 defines osteopenia. Risk factors include postmenopausal estrogen loss, corticosteroid use, smoking, low body weight, and inactivity.

Prevention and treatment teaching:

• Calcium 1,000-1,200 mg/day (diet preferred) plus vitamin D 800-1,000 IU/day
• Weight-bearing exercise (walking) and fall prevention — the fracture, not the density, is the danger
• Bisphosphonates (alendronate, risedronate) slow resorption. The administration pearls are heavily tested: take first thing in the morning with a full glass of plain water, at least 30 minutes before food or other medications, and remain upright (sitting or standing) for 30-60 minutes to prevent esophagitis and esophageal ulceration. Report jaw pain — osteonecrosis of the jaw is a rare complication, so dental work should be completed before starting therapy. Denosumab and raloxifene are alternatives

Osteoarthritis Versus Rheumatoid Arthritis

Nursing pearls: methotrexate requires monitoring for hepatotoxicity and bone marrow suppression and is contraindicated in pregnancy; biologics raise infection risk — screen for tuberculosis and hepatitis B before starting, and hold for active infection. Both diseases benefit from joint protection, balanced rest and activity, and heat for stiffness (RA) versus ice for acute inflammation.

Gout

Gout is deposition of monosodium urate crystals from hyperuricemia, causing sudden, exquisitely painful, red, hot joints — classically the great toe (podagra), often at night. Diagnosis is by urate crystals (needle-shaped, negatively birefringent) in joint fluid; serum uric acid may be normal during a flare.

• Acute flare: NSAIDs, colchicine (most effective within 24 hours of onset; watch for GI upset), or corticosteroids; rest and ice the joint; do not massage
• Chronic prevention: allopurinol lowers uric acid — teach patients not to start, stop, or change the dose during an acute flare (fluctuations worsen it), and report rash immediately (rare Stevens-Johnson syndrome)
• Diet: limit purine-rich foods (organ meats, shellfish, sardines, gravies), avoid alcohol especially beer, and maintain hydration of 2-3 liters/day to prevent urate kidney stones

Fractures and Their Complications

Fractures are classified as closed (skin intact) versus open/compound (skin broken — infection risk), and by pattern: transverse, oblique, spiral (twisting force), comminuted (bone shattered into fragments), greenstick (incomplete, in children), and compression (vertebrae). Initial care: immobilize the joint above and below, splint in position found (never attempt to realign in the field), apply ice, and assess distal neurovascular status before and after any intervention.

Three complications dominate the exam:

Fat Embolism Syndrome

Fat globules from a long-bone (especially femur) or pelvic fracture enter the circulation, classically 24 to 72 hours after injury. The triad is hypoxemia (the earliest and most dangerous sign — dyspnea, tachypnea, dropping oxygen saturation), altered mental status (confusion, agitation), and a petechial rash over the chest, axillae, and conjunctivae. Nursing priority is respiratory support — administer oxygen, position upright, monitor arterial blood gases, and prepare for possible ventilation. Early fracture stabilization is preventive.

Compartment Syndrome

Bleeding and edema within a closed fascial compartment compress vessels and nerves. Assess the 6 Ps:

1. Pain — out of proportion to the injury, unrelieved by analgesia, and worsened by passive stretch (the earliest and most reliable sign)
2. Paresthesia — numbness, tingling
3. Pallor
4. Pulselessness — a late, ominous sign
5. Paralysis — late
6. Poikilothermia — limb becomes cool

Actions: remove or loosen constrictive dressings, bivalve the cast as ordered, keep the limb at heart level — do NOT elevate above the heart (elevation reduces arterial inflow), avoid ice directly, and notify the provider immediately; definitive treatment is emergency fasciotomy. Delay beyond about 6 hours causes permanent muscle and nerve death (Volkmann's contracture).

Deep Vein Thrombosis

Fractures, surgery, and immobility create Virchow's triad (stasis, hypercoagulability, endothelial injury). Signs: unilateral calf or thigh swelling, warmth, and pain. Prevent with early mobilization, sequential compression devices, and anticoagulant prophylaxis (enoxaparin). A DVT that embolizes becomes a pulmonary embolism — sudden dyspnea, chest pain, tachycardia.

Neurovascular Checks

After any fracture, cast, or orthopedic surgery, perform neurovascular checks distal to the injury — typically every 15 to 30 minutes initially, then hourly, then every 4 hours — comparing with the unaffected limb. Assess the 5 Ps: color (pallor/cyanosis), warmth and capillary refill (normal under 2-3 seconds), pulses, sensation (numbness/tingling), and movement (can the patient wiggle fingers or toes?), plus pain character. Report changes immediately — nerve and vessel damage is time-limited.