Dynamic interface pressure distributions of two transtibial prosthetic socket concepts

In this study, we investigated and compared the dynamic interface pressure distribution of hands-off and hands-on transtibial prosthetic systems by means of pressure mapping. Of the 48 established unilateral amputees recruited, half (n = 24) had been wearing pressure-cast prostheses (IceCast Compact) and the other half (n = 24) had been wearing hand-cast sockets of the patellar tendon bearing design. We measured the dynamic pressure profile of more than 90% of the area within each prosthetic socket by means of four Tekscan F-Scan socket transducer arrays. We compared the interface pressure between socket concepts. We found that the distribution of dynamic pressure at the limb-socket interface was similar for the two intervention (socket prescription) groups. However, a significant difference was found in the magnitude of the interface pressure between the two socket concepts; the interface pressures recorded in the hands-off sockets were higher than those seen in the hands-on concept. Despite the differences in interface pressure, the level of satisfaction with the sockets was similar between subject groups. The sockets instrumented for this study had been in daily use for at least 6 months, with no residual-limb health problems.