The Common Peroneal Nerve and its Branches


	Head and Neck

	Vagus (X)

	Spinal Accessory Nerve (XI)

	Cervical Plexus (C2-4)

	Brachial Plexus (C5-T1)

	Upper Extremity

	Musculocutaneous

	Radial

	Median

	Ulnar

	Lower Extremity

	Ilioinguinal / Iliohypogastric

	Femoral

	Sciatic

	Common Peroneal

	Tibial

	Sural

The Common Peroneal Nerve and its Branches

The Common Peroneal Nerve in the Leg (prone with ankle supported)

The common peroneal nerve is a branch of the sciatic nerve and lies on the medial side of the common (conjoint) tendon of the biceps femoris muscle at the popliteal crease. The peroneal nerves can be imaged in the prone position with the knee flexed using a pillow under the ankle. The common peroneal nerve winds laterally around the neck of the fibula and then pierces the peroneus longus muscle. The common peroneal nerve flattens in shape as it passes over the fibular neck (Video 1.3 MB). This proximity to bone makes it vulnerable to injury at that location.

(Roll cursor over image to see labels.)

Superficial Peroneal Nerve

The superficial branch of the common peroneal nerve innervates the peroneus longus and brevis muscles of the lateral compartment of the leg. The superficial peroneal nerve tracks along the fascia between the lateral and anterior compartments of the leg to emerge by piercing the fascia lata and enter the subcutaneous tissues (see video above).

Deep Peroneal Nerve

The deep peroneal nerve arises in the substance of the peroneus longus muscle and enters the anterior compartment after piercing the fascial septum. The deep peroneal nerve joins the anterior tibial artery in the anterior compartment of the leg.

References

Heinemeyer O, Reimers CD. Ultrasound of radial, ulnar, median, and sciatic nerves in healthy subjects and patients with hereditary motor and sensory neuropathies. Ultrasound Med Biol. 1999 Mar;25(3):481-5. PMID: 10374990

Peeters EY, Nieboer KH, Osteaux MM. Sonography of the normal ulnar nerve at Guyon's canal and of the common peroneal nerve dorsal to the fibular head. J Clin Ultrasound. 2004 Oct;32(8):375-80. PMID: 15372443

Peer S, Kovacs P, Harpf C, Bodner G. High-resolution sonography of lower extremity peripheral nerves: anatomic correlation and spectrum of disease. J Ultrasound Med. 2002 Mar;21(3):315-22. PMID: 11883543

Gruber H, Peer S, Meirer R, Bodner G. Peroneal nerve palsy associated with knee luxation: evaluation by sonography--initial experiences. AJR Am J Roentgenol. 2005 Nov;185(5):1119-25. PMID: 16247119