Inaccuracy in the current methods of compartment syndrome diagnosis often leads to delays in treatment. Missed diagnosis of compartment syndrome to be 1 of the most common causes of litigation against doctors in North America, with the average malpractice award from a missed compartment syndrome case approximately $280,000 in 1993. In the absence of good diagnostic tools for compartment syndrome, anecdotal evidence suggests that the fasciotomy, a surgical opening of the muscle fascia to release compartment pressures is often performed prophylactically, subjecting the patient to a long and expensive recovery that might otherwise be avoided. The aim of this Phase I SBIR is to investigate whether the enhanced capabilities of Luna's Quantitative Ultrasound System (QUS) will result in improved correlation between an ultrasound-derived pressure factor and slit-catheter measurements of intramuscular pressure (IMP), the current gold standard measurement for diagnosing compartment syndrome. As part of this overall objective, we propose a series of modifications to Luna's QUS leading to a 1-month, 10-patient study at the UCSD Department of Orthopaedics in which IMP in the 4 compartments of the lower leg is temporarily raised through well-established models. [unreadable] [unreadable] [unreadable]