Predicting Acute Compartment Syndrome (PACS)

The long-term objective is to develop a tool to aid in making a timely and accurate diagnosis of acute compartment syndrome (ACS). The immediate objective is to develop a model to accurately predict the likelihood of ACS based on data available to the clinician within the first 48 hours of injury (specific clinical findings supplemented by muscle oxygenation measured by near-infrared spectroscopy (NIRS), and continuous intramuscular pressure (IMP) and perfusion pressure (PP) monitoring). Our primary outcome is the retrospective assessment of the likelihood of compartment syndrome made by a panel of clinicians using the following data: * A physiologic "fingerprint" composed of continuous pressure versus time curve, continuous oximetry values, response of muscle to fasciotomy when performed, and serum biomarkers of muscle injury (CPK levels). * Clinical and functional outcomes at 6 months post-injury including: sensory exam, muscle function, presence/absence of myoneural deficit, and patient reported function using the Short Musculoskeletal Function Assessment (SMFA).