The prosthesis socket may become loose because of
Morphologic changes in the residual limb (eg, atrophy, fluid volume change)
Mechanical problems with the prosthesis
Mechanical problems may be due to a loss of suspension or connection to the residual limb or body. A suction valve or vacuum pump may be malfunctioning. The suction or vacuum sealing sleeve may have developed a hole allowing air to enter and the prosthesis to slip off slightly. In upper limb cases, a harness or strap may have stretched or torn.
Patients typically have instructions from their prosthetist on how to troubleshoot problems with their specific prosthesis. If these steps do not remedy the problem, patients should see their prosthetist to assess and correct the problem and thus prevent injury to skin or loss of stability and falling.
(See also Overview of Limb Prosthetics.)