Below-knee amputation using a medial saphenous artery-based skin flap

A modified below-knee (BK) amputation with the medial saphenous artery-based skin flap coverage was designed to preserve a functional BK stump for those who were unable to receive the conventional long posterior flap or skew-type amputation.

In designing, the medial skin flap was outlined with the margins beginning 1 to 2 cm medial to the tibial crest to close to the middle of the posterior calf, with the length of the flap being equal to the transverse diameter of the leg at the anticipated level of bone section. The posterior margin of the flap was placed close to the middle of the posterior calf or adjacent to the interrupted posterior skin incision line. After elevation of the medial skin flap and performance of the rest of the procedure with the standard BK amputation methods, the posterior muscle mass was carried anteriorly to cover the bony stump and the medial skin flap was brought laterally to cover the defect.

This modified BK amputation was successfully done in a total of nine patients during the period January 1998 to January 2004. There were four females and five males, with ages ranging from 44 to 74 years (average 59.1 years). All the skin flaps survived completely without major complications, except for one patient who developed a wound infection.

With a skin flap that was perfused by a direct cutaneous vessel, saphenous artery, and innerved by the saphenous nerve, the medial saphenous artery-based flap used in the modified BK amputation comprises one valuable alternative when conventional techniques are unsuitable.