Lateral sural artery

The lateral sural artery is a direct muscular branch of the popliteal artery that supplies the lateral head of the gastrocnemius muscle in the posterior compartment of the leg. It typically originates at or above the level of the tibial plateau, alongside its counterpart, the medial sural artery. In some anatomic variants, the medial and lateral sural arteries may arise from a common trunk before dividing to supply their respective gastrocnemius heads.

Anatomic characteristics:

• Origin: The lateral sural artery arises from the popliteal artery, either as an independent branch or from a common trunk shared with the medial sural artery.

• Course: It descends to supply the lateral belly of the gastrocnemius muscle and gives rise to the superficial lateral sural artery, a cutaneous branch that pierces the crural (deep) fascia — typically 0 to 12 cm below the fibular head and approximately 3 cm lateral to the midline — to supply the overlying skin of the posterolateral calf.

• Caliber: The lateral sural artery is generally smaller in diameter than the medial sural artery. The superficial lateral sural artery has a reported diameter of approximately 0.4–2.5 mm, and the deep lateral sural vessel has a caliber of approximately 1.5–2.5 mm.

• Accompanying structures: The superficial lateral sural artery is typically accompanied by the lateral sural cutaneous nerve and one or two venae comitantes. The short saphenous vein runs medially, at a distance of 3.5–5 cm from the artery.

Clinical significance:

The lateral sural artery and its perforators are relevant in reconstructive microsurgery. The superficial lateral sural artery can serve as the pedicle for fasciocutaneous free flaps used in head and neck or extremity reconstruction. However, compared to the medial sural artery perforator (MSAP) flap, the lateral sural artery perforator flap is considered less reliable due to the smaller and more variable caliber of the lateral vessels. Anatomic studies have shown that a dominant lateral sural artery perforator is present in only about 31% of dissected legs, compared to 94% for the medial sural artery perforator, making preoperative perforator mapping (e.g., with duplex Doppler ultrasound) essential when planning lateral sural artery-based flaps.

Additionally, the lateral sural artery can anastomose with branches of the peroneal artery, forming a suprafascial vascular network that contributes to the cutaneous blood supply of the posterolateral calf.