In the past 5 years, a great deal of time and effort has been expended in an effort to better define clinical, anatomic, and laboratory parameters of CECS. It is now a well-recognized entity and one that can be readily resolved with fasciotomy. But the reasons for predisposition and the pathophysiologic mechanisms remain obscure. It appears, however, that basing the decisions for fasciotomy on clinical characteristics alone leads to overdiagnosis and excessive surgery. In this series, almost 50% of the referred subjects failed to demonstrate adequate laboratory criterion for the diagnosis of CECS. Fasciotomy in these patients may have effected a cure, but the reasons may be unrelated to increased intracompartmental pressure. Furthermore, in the laboratory diagnosis of CECS, the rate of return to resting compartment pressure following exercise seems more accurate than reliance on resting pressure alone. 31P-NMR has proved valuable in the dynamic assessment of muscle ischemia as reflected by relative PCr concentrations. Finally, although a mechanism explaining the source of pain has not been established by this study, it appears that ischemia is not a significant factor.