Socket and Suspension Systems

Socket Systems

Style and fit will be unique to the patient’s needs and activity level. There are many systems available; each option will be discussed at length during your visit. At POSI, we encourage and welcome your participation in the design process. Our practitioners have experience working with a variety of socket designs for each level of amputation. Designs are chosen on an individual basis from information gathered during your initial evaluation.

Socket Fit

Socket fit has the biggest impact on success in rehabilitation. Additionally, there is a correlation between proper fit and perceived weight. Well-fitting sockets should have increased proprioceptive feedback, anatomical control, decreased energy expenditure, total contact, and most of all, be comfortable.

Suspension

Closely related to the design of the socket is the suspension, or how the socket remains in place on the patient’s limb. Suspension mechanisms are incorporated as part of socket design, and will therefore be chosen prior to casting. Suspension can be achieved through a mechanical lock, suction, or capture of the anatomy. Mechanical lock is achieved by the incorporation of a pin or lanyard attached at the end of a roll on liner which engages into a lock in the socket. Suction suspensions are achieved through a number of methods including seal-in liners and direct skin contact. In addition, air may be evacuated via pump to achieve elevated vacuum. Anatomical suspension is achieved when the contours of the socket capture and hold onto the contours of the patient’s body. Each of these systems have advantages and disadvantages which will be discussed with the patient.

Symptoms of Poor Fitting Socket:

  • Unable to progress to expected goals
  • Pain
  • Feels like it is a lot of effort and concentration to walk
  • Poor confidence/ balance
  • Skin breakdown, callus, or unusual discoloration
  • Significant space between residual limb and socket in standing position
  • Inability to balance or transfer weight to prosthesis without fear or pain

Socket fit determines the potential outcome, regardless of the components and efforts of medical team!

Poor fitting socket = poor gait = poor outcome

  • Components will be unable to be used to their full potential
  • Regardless of your and your medical team’s efforts, you will be unable to achieve goals
  • Increased risk of damage to skin and joints
  • Increased energy expenditure