ABSTRACT: BACKGROUND: Prompt diagnosis and decompression of acute lower extremity compartment syndrome (LECS) in the multisystem injured patient is essential to avoid the devastating complications of progressive tissue necrosis and amputation. Despite collaborative trauma and orthopedic management of these difficult cases, significant delays in diagnosis and treatment occur. Periodic system review of our trauma and orthopedic data for complications of LECS led us to hypothesize that delayed diagnosis and limb loss were potentially preventable events in our trauma center. SETTING: Academic level 1 trauma center. METHODS: We performed a prospective review of our trauma registry for all cases of LECS over a 7 year period (2/98-10/2005). Variables reviewed included demographics, injury patterns, tissue necrosis, amputation and mortality. RESULTS: Eighty-three (10 female, 73 male) cases were reviewed. Mean age = 33.3 years (range 1-78). Mean ISS = 19.4, GCS = 12.5. Five (6.0%) had amputations; 7 (8.4%) died. Fractures occurred in 68.7% (n = 57), and vascular injuries were present in 38.6% (n = 32). In 7 patients (8.4%), a delayed compartment release resulted in muscle necrosis requiring multiple debridements, subsequent wound closure problems, and long term disability. Of note, none of these patients had prior compartment pressure measurements. Furthermore, 6 patients (7%) had superficial peroneal nerve transections as complications of their fasciotomy. CONCLUSION: In the multisystem injured patient, LECS remains a major diagnostic and treatment challenge with significant risks of limb loss as well as complications from decompressive fasciotomy. These data underscore the importance of routine surveillance for LECS. In addition, a thorough knowledge of regional anatomy is essential to avoid technical morbidity.