Total surface bearing self suspending above-knee sockets

A new type of above-knee socket has been designed to provide total surface support and to dispense with ischial bearing as the primary weight bearing area. The socket is based upon the hypothesis that if the soft tissues of an above-knee stump are adequately supported in a suitably shaped container they will behave under load as an elastic solid with low stiffness. A method has been devised for taking the cast for the new type socket using an elastic sleeve as a "compliant socket". The grip of the elastic sleeve and the use of traction weights deform the stump tissues to the required shape while the cast is setting. The results of laboratory measurements of the transinterface pressures in these sockets under axial loading conditions have correlated well with the figures forecast by calculation. The new socket is now available to patients at a number of Centres in England.