6.6 Musculoskeletal: Mobility, Falls & Compartment Syndrome

Musculoskeletal: Mobility, Falls & Compartment Syndrome

Musculoskeletal issues in progressive care are frequently framed as minor compared to cardiac or respiratory crises, but immobility complications, falls, and compartment syndrome carry serious morbidity, and compartment syndrome specifically is a limb- and life-threatening emergency where minutes matter.

The Cost of Immobility

Bed rest and critical illness rapidly produce ICU-acquired weakness, muscle atrophy, and deconditioning, compounding the risk of pressure injuries, venous thromboembolism, atelectasis, and delirium. Functional decline from immobility can be as dangerous as the acute illness itself, extending length of stay and reducing the odds of returning to independent function. This is why early mobility protocols — getting patients out of bed, dangling, standing, or ambulating as soon as hemodynamically and neurologically appropriate, even while intubated when feasible — have become a core progressive and critical care quality metric. Early mobility is one component of the ABCDEF bundle alongside spontaneous awakening and breathing trials, delirium monitoring, and family engagement, and it directly reduces delirium duration and ICU length of stay.

Falls and Gait Disorders

Hospitalized progressive care patients face elevated fall risk from generalized weakness, orthostatic hypotension, sedating medications, unfamiliar environments, tethering devices such as IV lines, catheters, and telemetry leads, and underlying gait disorders. Falls risk assessment on admission and with any status change, coupled with interventions such as bed alarms, non-slip footwear, scheduled toileting, and involving physical therapy for gait training, are standard prevention measures. A fall in a patient who is also anticoagulated carries added urgency, since even a minor fall can precipitate significant bleeding, particularly intracranial hemorrhage — any fall with head strike in an anticoagulated patient warrants prompt neurologic assessment and often imaging regardless of how well the patient appears immediately afterward.

Compartment Syndrome

Compartment syndrome occurs when pressure within a closed fascial compartment, most often in the lower leg or forearm, rises high enough to compromise capillary perfusion to the muscles and nerves inside — a true surgical emergency, most commonly following fractures, crush injuries, reperfusion after vascular repair, or tight casts or dressings. The classic "6 Ps" describe the clinical picture:

Because pulselessness is a late sign, waiting for pulses to disappear before acting risks irreversible muscle and nerve necrosis within hours. Definitive diagnosis uses direct intracompartmental pressure measurement; elevated pressure, generally within about 30 mmHg of diastolic blood pressure and reflecting inadequate perfusion pressure, combined with the clinical picture prompts emergent fasciotomy to relieve pressure and preserve the limb. Nursing responsibilities include frequent neurovascular checks (pain, pulses, motor function, sensation, capillary refill) distal to any fracture, cast, or vascular injury, and immediately reporting any escalating pain, especially pain with passive stretch of the affected muscles, rather than waiting for other signs to develop.

Rhabdomyolysis

Rhabdomyolysis is the breakdown of skeletal muscle releasing intracellular contents, including creatine kinase (CK) and myoglobin, into the bloodstream, often triggered by crush injury, prolonged immobilization or downtime, compartment syndrome, seizures, or certain medications. Myoglobin is directly nephrotoxic and can precipitate in renal tubules, so rhabdomyolysis is a leading cause of preventable acute kidney injury. Clinical clues include markedly elevated CK, dark tea- or cola-colored urine, and muscle pain or weakness. Treatment centers on aggressive isotonic IV fluid resuscitation to maintain high urine output and flush myoglobin through the kidneys, along with close monitoring for hyperkalemia from muscle cell lysis and other electrolyte shifts that can trigger dangerous arrhythmias.

Fractures and Fat Embolism Syndrome

Fracture care in progressive care focuses on stabilization (splinting, traction, or surgical fixation), pain control, and serial neurovascular checks of the affected extremity — pain, pulses, motor function, sensation, and capillary refill — to catch both compartment syndrome and simple vascular compromise from swelling or malpositioning. Any immobilized fracture patient also needs venous thromboembolism prophylaxis, since fracture and prolonged immobility are both independent clot risk factors.

Fat embolism syndrome is an underrecognized complication most often following long-bone fractures (especially femur) or major orthopedic surgery, in which fat globules from bone marrow enter the circulation and lodge in the pulmonary and systemic microvasculature. It classically presents 24 to 72 hours after injury with a triad of respiratory distress, neurologic changes (confusion, agitation), and a petechial rash, typically over the chest, axillae, and conjunctivae. Because the onset is delayed rather than immediate, new hypoxia or altered mental status in a fracture patient a day or two after injury should raise suspicion for fat embolism syndrome rather than being dismissed as unrelated to the orthopedic injury. Management is supportive — oxygenation, hemodynamic support, and early fracture stabilization to limit further fat release — since there is no specific reversal treatment.