This nerve arises from the common peroneal (fibular) nerve, runs through the peroneus longus muscle, and extends between the peroneus longus and brevis muscles. In the distal half of the leg, the nerve is sandwiched between peroneus brevis and extensor digitorum longus in the intermuscular septum that separates the anterior and lateral compartments of the leg and gradually ascends into a superficial location before eventually piercing the crural fascia. Subcutaneously, or still at the subfascial level, it divides into the thicker medial dorsal cutaneous nerve and the smaller intermediate dorsal cutaneous nerve, providing the sensory supply for the skin on the back of the foot and the toes.

This nerve runs between the tibialis anterior muscle and the extensor hallucis longus muscle in the direction of the ankle, where it divides into a medial and a lateral end branch. The medial end branch continues in the same direction as the nerve trunk and passes with the dorsalis pedis artery to the first interosseous space, crossing under the tendon of the extensor hallucis brevis muscle to the distal end of the interosseous space. Here it joins with a strand of the superficial peroneal nerve and divides into the end branches for the facing sides of the dorsal surfaces of the first and second toes. The lateral end branch turns laterally and supplies the extensor digitorum brevis muscle, sending off three interosseous nerves.

The medial sural cutaneous nerve arises in the proximal part of the popliteal fossa, runs down between the two heads of the gastrocnemius muscle, and joins the peroneal communicating branch (lateral sural nerve) to form the sural nerve. Accompanied by the small saphenous vein, the sural nerve runs behind the lateral malleolus and is contained within the same superficial fascial sheath. It passes as the lateral dorsal cutaneous nerve along the lateral side of the foot, where it gives off a connecting branch to the intermediate dorsal cutaneous nerve and ends as the dorsalis digiti minimi nerve on the lateral edge of the dorsum of the small toe.

Behind the lateral malleolus, it sends off branches (the lateral calcaneal branches) to the skin there and at the heel. The branches for the lateral side of the ankle, for the anterior capsular wall, and for the tarsal sinus originate proximal to the malleolus.

Below the knee, it runs along the tibial surface close to the great saphenous vein. Its relationship to the saphenous vein is inconstant, and the nerve may be either posterior or anterior to the vein. A common fascia has been described that envelops both the vein and the nerve in the distal third of the calf. At the level of the lower leg, the saphenous nerve courses along the medial side of and anterior to the medial malleolus and sends off branches to the skin of the medial side of the foot. It usually ends in the metatarsal area, without reaching the big toe.

As all the five ankle nerves are superficial nerves, linear high-frequency ultrasound probe is used.