Many disabled persons who have hands that are capable of functioning well are prevented from using them due to the loss of shoulder, arm, and forearm muscle power as a result of poliomyelitis or other causes. Electrically controlled slings can aid such severely disabled persons to adapt to their home and work environments. These electromechanical slings allow the person's arms to be placed in a wide variety of functional positions, from a 90-degree elbow flexion at a table level for the beginning phase of eating or working to a 90-degree shoulder flexion for such activities as reaching for food on the upper shelf of a cupboard or tools on a high ledge (fig. 1).
The slings can be lowered to a level where the person can independently "crawl" or be placed into the elbow and forearm slings; then, by the use of a switch, the arms are brought to the