Elements of the Prosthesis

Structural Interface

The structural interface is the part of the prosthesis that the body connects to in order to interact with the environment.  It also connects the body to the artificial aspects of the prosthesis.  The “socket” is the name that is most often used to describe this part of the prosthesis

Soft Tissue Interface

Prosthetic socks and liners are examples of soft tissue interfaces.  Worn next to the skin these types of interfaces provide a barrier between the body and the structural interface to allow for movement and the changing nature of the human body.  The ability to add or take away plys of socks allows the patient to maintain a safe functional interface with the socket and allows for maximum comfort and the health of the skin.

Joint Systems

A prosthesis, depending on the level of amputation, includes the replacement of joints.  Feet, ankles, knees and hips are the joint systems for lower limb prostheses; Hands, wrists, elbows and shoulders are the joint systems for upper limb prostheses.

Skeletal Components

The parts of the prosthesis that connect the joint systems and the structural interface (socket) are called skeletal components.

Suspension Systems

Suspension systems are used to hold the prosthesis onto the body.  There are many different types of suspension including suspension sleeves or seals, belts, distal pin and locking systems, vacuum systems and suction valves.  The type of suspension is determined individually for each patient based on their needs and activity levels.

Control Systems

Prostheses are primarily mechanically controlled by body power.  However, there are innovations in myo-electric, microprocessor and bionics that enable some prostheses to have externally power controlled assistance.