When a non-articulating foot is used, there is very little maintenance required for the below-knee prosthesis other than keeping it clean inside and out. Articulated feet generally need to be lubricated at regular intervals. The heel height of the shoe is a very important factor in the alignment of the prosthesis. Therefore, when shoes are changed, it is important that the effective heel height be the same as on the shoes used previously. The effective heel height is obtained by subtracting the thickness of the sole (B) from the apparent heel height (A) as shown below.
For the same reason, the heels of the shoes should be replaced frequently so that wear will not result in alignment changes.
Also, a badly worn shoe will increase the wear on a prosthetic foot. Prostheses should not be worn without shoes. Not only will the temporary misalignment cause excessive stress on the stump and knee joint, but the wear on the foot will result in permanent misalignment. Most prostheses are water-resistant but few are waterproof. If the foot becomes wet, the shoe should be removed as soon as possible to facilitate drying.
When the amputee has any doubt about the fit, alignment, or condition of the prosthesis or stump, he should consult with his prosthetist immediately