The creation of the prosthetic socket, which is based on a model of your body, is the first step in fabricating a prosthesis. The socket is arguably the most important part of a prosthetic limb. A prosthesis with an improperly fitting socket may end up in the closet, regardless of high-tech knee or foot components. Even worse, it can put you at risk. A prosthesis that is not fitting well can cause skin breakdown, instability, and a lack of confidence.
A prosthesis with an improperly fitting socket may end up in the closet, regardless of high-tech knee or foot components. Even worse, it can put you at risk
The most common reason for an ill-fitting socket is volume changes in your limb. This is especially common during the months following amputation. As swelling reduces, the shape of the limb changes. Bones become more prominent and muscles shift. As your limb reduces in volume, its position inside the socket will change.
During your follow up appointments, your prosthetist will adjust your socket fit to address these changes in your limb. For example, the prosthetist may add padding or adjust the number of socks you wear with your prosthesis. “Trying different socks is the first line of defense in making sure the prosthesis is fitting snug and not rotating,” explains Bio-Tech’s Jim Druwe, CPO. “It will also prevent you from ‘bottoming-out’.” ‘Bottoming-out’ refers to pressure at the bottom of the residual limb as it falls further into the socket.
Sock Ply 101
Silicone locking and cushion liners involve the use of prosthetic socks. You will receive a collection of socks of different thicknesses when you receive your prosthesis. You and your prosthetist will decide the best combination of socks that result in a secure and comfortable fit. Many people experience volume changes throughout the day. In the morning your socket may feel comfortably snug and then by the end of the day it may feel too loose. Signs that you have reduced in volume may include your limb moving around inside the socket, pistoning, and ‘bottoming-out’. You may need to add one or more socks. If you experience an increase in swelling, you may need to reduce the number of socks or use a thinner sock.
“Trying different socks is the first line of defense in making sure the prosthesis is fitting snug and not rotating,” explains Bio-Tech’s Jim Druwe, CPO.
You may notice that the shape and size of your limb becomes more stable as you progress in your prosthetic rehabilitation. Even so, you can expect to continue to experience minor changes in your limb throughout the day. Weight gain and weight loss can also affect your socket fit in the future. A healthy, stable diet can go a long way towards helping your rehabilitation. ‘Yo-yo dieting’ can pose a real challenge to maintaining a properly fitting socket.
Ultimately, sock ply management and socket adjustments can only take you so far. If the change in your limb is significant, it may be time for a new socket.