Prosthetic principles in bilateral shoulder disarticulation or bilateral amelia.

Following a brief survey of the historic development of pneuma­ tic prostheses the actual principles of prosthetic management in bi­ lateral shoulder disarticulation or bilateral amelia are explained. The active functions are re­ stricted to active pronation and supination, active gripping of the terminal device "hook" or "hand", combined with pneumatic locking of free swinging shoulder and elbow joints in one artificial arm; the cosmetic arm provides only space for the power package in the resin socket of the upper arm. Both arms are suspended on a Simpson frame. Thus optical control is concen­ trated on the movements of the functional arm. The reduction of valve control makes prosthetic training and use easier. Recently hybrid systems came into use because electric power proved superior to pneumatic power for pronation and supina­ tion and gripping, whereas C O 2 is still necessary for locking the elbow and the shoulder joint. The accum­ ulator can be recharged daily at a plug socket, the CO2 container need only be refilled after one or two weeks ensuring more indepen­ dence for the disabled. The advan­ tage of such a prosthesis is the bet­ ter appearance in public combined with a certain functional use. However only intensive foot training without prostheses pro­ vides independence in daily acti­ vities, because even sophisticated prosthetic systems cannot make up completely for body loss.