Acute compartment syndrome of the thigh has been reported infrequently. To date, only eight cases from isolated blunt trauma without fracture have been reported. Two additional cases caused by intramuscular hematomas following blunt, low-energy trauma, which were treated successfully with emergency fasciotomies, are presented. The morbidity from this syndrome varies from mild, with quadriceps weakness, fatigue, and myositis ossificans, to severe, with limb-threatening vascular compromise. Morbidity can be avoided if a high level of suspicion is maintained, compartment pressures are measured, fasciotomies are performed, and hematomas are drained. Postoperatively, patients can expect a dramatic decrease in pain and a quick return of quadriceps function with aggressive physical rehabilitation.