Most amputees (especially new amputees) experience many changes in their residual limb. Typically, your limb will reduce in volume and size, because walking with a prosthesis enhances your circulation and helps remove excess fluid from its tissues. Additionally, your limb can re-contour, or change in shape, simply from wearing a prosthesis for a while.
Over the long term, some of the musculature in your residual limb may atrophy (get smaller). Your body is constantly changing in response to pressures that are applied to it. Some of your muscles in your residual limb aren’t attached to the body parts they used to be attached to, and these muscles no longer do the same jobs they used to, so they get smaller over time.
Most of these changes in your residual limb can be accommodated by following up with your prosthetists for adjustments to the socket. If the changes in your limb are too great for your prosthetist to adjust the socket, it may be time for a new prosthetic socket or an entirely new prosthesis.