Clinical study: Changes in interface pressure and stump shape over time: Preliminary results from a transtibial amputee subject

Interface stresses and stump shape were measured during sessions over a twomonth interval on a transtibial amputee subject. Results from thirteen transducer sites monitored during four sessions showed greater interface pressure changes over time at anterior sites than at lateral or posterior locations. There was a trend of decreased pressure with stump swelling and increased pressure for stump atrophy. During one session in which stump shape was monitored over a 23.1 min interval after ambulation, stump swelling was localised. Swelling tended to increase in the regions of initial enlargement, as opposed to redistributing through different areas over time. Regions of swelling were anterior lateral and posterior proximal, areas of thick underlying soft tissue. Identification of localised areas of swelling and atrophy and understanding of their effects on interface pressures could be used to improve individual socket design.

[1]  S G Zachariah,et al.  Automated hexahedral mesh generation from biomedical image data: applications in limb prosthetics. , 1996, IEEE transactions on rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society.

[2]  L Bennett,et al.  Stump-socket pressure in lower extremity prostheses. , 1968, Journal of biomechanics.

[3]  P J Holliday,et al.  Volume fluctuations in the residual limbs of lower limb amputees. , 1982, Archives of physical medicine and rehabilitation.

[4]  J. Sanders,et al.  Effects of alignment changes on stance phase pressures and shear stresses on transtibial amputees: measurements from 13 transducer sites. , 1998, IEEE transactions on rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society.

[5]  R L Lieber,et al.  Volume changes occurring in postoperative below-knee residual limbs. , 1988, Journal of rehabilitation research and development.

[6]  S G Zachariah,et al.  A modular six-directional force sensor for prosthetic assessment: a technical note. , 1997, Journal of rehabilitation research and development.

[7]  Joan E. Sanders,et al.  A silhouetting shape sensor for the residual limb of a below-knee amputee , 1995 .