How will a prosthesis stay on?

See below: This depends on what body part the prothesis is for. Most arm/leg prosthetics rely on a custom harness, a suction interface, or a sleeve with interlocking pin.

Suspension : Prosthetic arms or legs are attached to the body several ways. The goal is to protect the skin while remaining safely in place. Most systems these days relay on a sleeve or liner to protect the skin that works with a lanyard, pin, strap or a suction system to hold the prosthesis in place.