The Medial Sural Artery Perforator Flap in Lower Extremity Reconstruction.

Medial sural artery perforator (MSAP) flap is a thin, pliable, and versatile flap. It is a fasciocutaneous flap with chimeric design capacity. The donor site permits the synchronous harvesting of nonvascularized tendons and nerves. Free MSAP flap is suitable for foot, ankle, and distal one-third of the leg reconstructions. Pedicled MSAP flap is an alternative flap for knee and proximal two-thirds of leg defects, covering classical lower limb reconstruction territories of soleus, medial, and lateral gastrocnemius muscle flap. Computed tomography angiography, indocyanine green, and endoscopic-assist dissection enhances MSAP flap surgical planning and reduces its technical adversities and complications.