Failure of a gastrocnemius muscle flap due to an isolated high-grade stenosis of the sural artery.

The gastrocnemius muscle is highly reliable for flap coverage of defects of the knee or upper third of the leg. Pathology or injury to its dominant arterial pedicle is rare, so preoperative testing is usually not required when distal pulses are present. In this case, an unsuspected high-grade stenosis of the origin of the sural artery was the cause of failure of the flap and made it necessary to use a free flap for salvage. This case raises questions as to the need for preoperative or intraoperative assessment of patency and/or perfusion pressure of the flap vascular supply.