Sural nerve
The sural nerve arises within the popliteal fossa following the union of the medial sural cutaneous nerve from the tibial nerve and sural communicating nerve from the common peroneal nerve. In some cases, due to anatomical variation, this union does not occur and instead, the sural nerve arises as a direct branch of the tibial nerve. The sural nerve becomes cutaneous midway down the leg by piercing the deep fascia of gastrocnemius. It then passes inferiorly through the leg along the lateral margin of the tendo achilles. As it continues along the lateral margin of the foot, it becomes known as the lateral dorsal cutaneous nerve and then as the tenth dorsal digital nerve proper as it innervates the fifth digit. Note that the sural nerve gives rise to the lateral calcaneal nerve which supplies the skin of the lateral heel. The sural nerve is generally palpable posterior to the lateral malleolus or along the lateral shaft of the fifth metatarsal.