Viscoelastic measurements in soft tissue

Summary form only given. A study was made of viscoelastic changes in the limb in the presence of the compartment syndrome, which can occur when muscle tissues swell following trauma. Measurements were made of the applied pressure-volume displacement curves with a 1.4-cm² indenter placed on the limb surface above the compartment. The noninvasively measured viscoelastic departure from purely elastic behavior at mid-pressure-cycle (60 mm Hg) dropped from 156 to 32 mm³ as compartment pressure increased from 6 to 63 mm Hg. Measurements were also taken in a study of ten normal human subjects. The use of matched sites was found to provide compensation for differences in fat content and muscle tone among subjects. In continuing studies of patents with the compartment syndrome, matched differences in A2 have been observed to correlate well with differences in compartment pressure. The noninvasive test provides an easy-to-use approach for diagnosing the compartment syndrome and for evaluating the time course of pressure changes in the limb