MRI investigation of musculoskeletal action of transfemoral residual limb inside a prosthetic socket

Amputation of an extremity is followed by changes in musculoskeletal structures of the leg. The understanding of the manner of how the remaining muscles control the prosthesis will increase our knowledge on the biomechanics of the stump/socket system and help in the design of a good prosthetic fitting. To learn about the changes appearing in the geometry of stump, muscles and bone after above-knee (AK) amputation and their changes during stump actions, transverse magnetic resonance images (MRI) have been obtained for both amputated and contralateral legs of three AK unilateral amputees. The 2D images showed that the shape of the limb changed and the muscles atrophied after amputation. During stump actions, the positions and geometry of the stump, bone and muscles also changed.