Interface pressures and shear stresses: sagittal plane angular alignment effects in three trans-tibial amputee case studies

Interface pressures and shear stresses at different sagittal plane angular alignment settings were measured on 3 trans-tibial amputee subjects ambulat ing with patellar-tendon-bearing total contact prostheses. Substantial sock et-shank angular alignment modifications in the sagittal plane had minimal effect on stance phase peak interface pressures. though more substantial ef fects on stance phase peak resultant shear stresses. No consistent trend of a greater stress at misaligned vs nominally aligned settings was identifie d. Changes in interface stresses from session to session tended to be great er than those for different alignment settings, suggesting that subjects co mpensated well for misalignments but less well for session differences.