Snapshot A 21-year-old, previously healthy man presents for evaluation of a painful left leg approximately 5 hours after his leg got caught between closing elevator doors. He did not have pain immediately after the leg trauma. However, he currently has 10/10 pain. Physical exam reveals pain with dorsiflexion of his left foot and tenderness in his calf. Posterior tibial and dorsalis pedis pulses are present bilaterally. The surgical service is consulted immediately for urgent fasciotomy of his left foot. Introduction Clinical definition a painful emergency condition that occurs when the tissue pressure inside an anatomical compartment, bound by fascia, exceeds the perfusion pressure, resulting in ischemia and necrosis Epidemiology Location lower extremity > upper extremity leg forearm hand foot thigh Risk factors trauma anticoagulation therapy bleeding disorders Etiology The most common cause is a fracture tibia fracture Soft tissue injury Circumferential burns Crush injuries Constrictive dressing (e.g., splints, casts, or poor surgical positioning) Penetrating wounds Pathogenesis blood flow is blocked when the tissue pressure exceeds the perfusion pressure within a fixed-volume compartment this results in a lack of oxygen and the accumulation of waste products, causing pain and decreased peripheral sensation irreversible tissue damage occurs between 6-8 hours after onset after a period of ischemia, tissue reperfusion generates toxic reactive oxygen species and other inflammatory mediators that cause increased capillary permeability and interstitial edema increased edema leads to rising compartment pressures, which can cause compartment syndrome limb ischemia-reperfusion injury Presentation Symptoms burning pain out of proportion to the injury the most specific and important symptom pain with active contraction of the compartment may have paresthesia or numbness Physical exam firm, swollen, and wooden feeling of the muscles on palpation may have skin findings such as bullae ↓ vibration sensation ↓ 2-point discrimination 6 P’s only manifest in the late stages of the syndrome Pallor Pain out of proportion worse with passive stretch Paresthesia “pins and needles” sensation Pulselessness Poikilothermia Paralysis Imaging Radiography indication typically not needed for diagnosing compartment syndrome, but useful for characterizing any trauma such as fractures Studies Compartment pressure measurement indication to confirm the diagnosis if clinicians are unable to elicit the symptoms or history modality the transducer is connected to a catheter and is used to measure the intracompartmental pressure (ICP) Making the diagnosis most cases are clinically diagnosed or guided by pressure measurement absolute ICP > 30 mm Hg Δ pressure (diastolic blood pressure - ICP) < 30 mmHg normal ICP is 0 mm Hg Differential Cellulitis distinguishing factor normal neurovascular exam Rhabdomyolysis distinguishing factors abnormal laboratory evaluation, including creatine phosphokinase, renal function studies, urine myoglobin, and potassium Treatment Management approach management is focused on early decompression observation and conservative management is appropriate only if ICPs are not high Conservative place limb at the level of the heart without elevation indication for all patients while awaiting diagnosis or decompression immediate removal of any wraps, splints, or casts indication for all patients immobilization indication for all patients Operative fasciotomy indications ICP > 30 mm Hg (with lower threshold for compartment syndrome of the hand) prolonged duration of compartment syndrome > 8 hours Complications Volkmann contracture permanent nerve and muscle damage Acute kidney injury Prognosis Higher chance of regaining function of the affected limb if a fasciotomy is performed within 12 hours