Fundamentals of Medial Sural Artery Perforator Flap

The medial sural artery perforator (MSAP) flap is a cutaneous flap found overlying the medial head of the gastrocnemius muscle, whose circulation depends on the latter’s musculocutaneous perforators. Unfortunately, anomalies are commonplace as true with most other perforator flaps, so no schematic exists to facilitate their pre-operative identification. If a relatively thin free flap is sought for a small- or moderate-sized defect that requires a long pedicle with larger caliber vessels, regardless of the position of the patient on the operating table, the MSAP flap may be a preferable option. This has proven most useful as a local flap alternative to the medial gastrocnemius muscle, or as a free tissue transfer for the hemi-tongue or ipsilateral lower extremity defect. Yet, the donor site sequela, even if only a conspicuous calf scar much less if skin grafted, is a major contraindication. Some, nevertheless, consider this a “workhorse” flap for general use throughout the body; but probably more restrictive usage would still be a legitimate consideration.