Mechanical aids for alignment of lower-extremity prostheses.

IF A prosthetic device is to give optimum service to the amputee, it must always be properly fitted, regardless of its mechanical excellence. This is especially true in the case of the lower extremity, where the prosthesis must function continually and where poor fit or alignment will lead quickly to rejection of the device by the wearer. Among prosthetists there seems to be general agreement that by far the most important factors in the success of any artificial leg relate to fit and alignment on the subject. Fit and alignment are usually considered together, since they are mutually interdependent. Over the years many different mechanical devices to aid in fitting and alignment of lower-extremity prostheses have been developed to help in the application of one or another particular set of alignment principles in use by individual titters. Others of these devices are more general in application and are adaptable for use by any prosthetist regardless of the particular alignment principles he advocates. In every case, however, an attempt has been made to improve the fitting and alignment technique by adopting one definite set of principles and using a mechanical device to aid in the application of those principles.