Design Of A Prosthetic Elbow For Elbow Disarticulation Amputations

Long above elbow and elbow disarticulation amputations pose a problem in fitting as the residual limb is nearly the same length as the upper arm on the sound side. Although these problems have been recognized for some time, no currently available elbows offer a complete solution. Conventional fittings, whether they einploy an elbow system attached to the end of the socket or use outside hinges, either make the limb geometry unnatural or restrict the ability to provide humeral rotation and a powered joint. The objective of the work described in this paper is to develop prosthetic elbowsfor long above elbow amputations which do not have these limitations Our work, as described here, has focused on multi-link mechanisms much as are used for knee disarticulation prostheses. The additional challenge in the upper limb case is to provide active locking of the joint, which is not usually a re,quirement other than at full extension for the knee, and to provide for powered operation.