summary Thigh Compartment Syndrome is a devastating lower extremity condition where the osseofascial compartment pressure rises to a level that decreases perfusion to the thigh and may lead to irreversible muscle and neurovascular damage. Diagnosis is made with the presence of severe and progressive thigh pain that worsens with passive knee motion. Firmness and decreased compressibility of the compartments is often present. Needle compartment pressures are diagnostic in cases of inconclusive physical exam findings and in sedated patients. Treatment is usually emergent fasciotomies of all 3 compartments. Epidemiology Anatomic location May occur anywhere that skeletal muscle is surrounded by fascia, but most commonly leg forearm hand foot thigh (details below) buttock shoulder paraspinous muscles Etiology Pathophysiology local trauma and soft tissue destruction > bleeding and edema > increased interstitial pressure > vascular occlusion > myoneural ischemia Causes trauma (most common) ipsilateral femur fractures increased incidence with open fractures crush injuries contusions gunshot wounds tight casts, dressings, or external wrappings extravasation of IV infusion burns postischemic swelling bleeding disorders arterial injury Anatomy 3 thigh compartments anterior compartment muscles quadriceps sartorious nerves femoral nerve posterior compartment muscles hamstrings nerves sciatic nerve adductor compartment muscles adductors nerves obturator nerve Presentation Symptoms pain out of proportion to clinical situation is usually first symptom may be absent in cases of nerve damage pain is difficult to assess in a polytrauma patient and impossible to assess in a sedated patient difficult to assess in children (unable to verbalize) Physical exam pain w/ passive stretch is most sensitive finding prior to onset of ischemia must test each compartment separately anterior compartment pain with passive flexion of knee posterior compartment pain with passive extension of knee medial compartment pain with passive abduction of hip paraesthesia and hypoesthesia indicative of nerve ischemia in affected compartment paralysis late finding full recovery is rare in this case palpable swelling peripheral pulses absent late finding amputation usually inevitable in this case Imaging Radiographs obtain to rule-out fracture Studies Compartment pressure measurements indications polytrauma patients patient not alert/unreliable inconclusive physical exam findings relative contraindication unequivocally positive clinical findings should prompt emergent operative intervention without need for compartment measurements technique should be performed within 5cm of fracture site or area of maximal swelling must test each compartment separately Diagnosis Clinical based primarily on physical exam in patient with intact mental status Treatment Nonoperative observation indications delta p > 30, and presentation not consistent with compartment syndrome Operative emergent fasciotomy of all affected compartments indications clinical presentation consistent with compartment syndrome compartment pressures within 30 mm Hg of diastolic blood pressure (delta p) intraoperatively, diastolic blood pressure may be decreased from anesthesia must compare intra-operative measurement to pre-operative diastolic pressure contraindications missed compartment syndrome Techniques Thigh fasciotomies approach anterolateral incision over length of thigh technique single incision technique for anterior and posterior compartments incise fascia lata expose and decompress anterior compartment retract vastus lateralis medially to expose lateral intermuscular septum incise lateral intermuscular septum to decompress posterior compartment may add medial incision for decompression of adductor compartment Complications Associated with significant long-term morbidity over 50% will experience functional deficits including pain decreased knee flexion myositis ossificans sensory deficits decreased strength