Quick Facts
Origin: Femoral nerve (L3-L4).
Course: Descends through the adductor canal and pierces the deep fascia to become cutaneous around the knee joint. It then descends with the great saphenous vein in the leg.
Branches: Infrapatellar and medial crural cutaneous branches.
Supply: Prepatellar skin and the skin over the medial leg.
Related parts of the anatomy
Origin
The saphenous nerve, the longest nerve in the body, arises from the anterior division of the femoral nerve.
Course
The saphenous nerve descends in the femoral triangle, lateral to the femoral artery, and enters the adductor canal (Romanoff et al., 1989). Here, the nerve crosses the femoral artery so that it lies medial to it. However, unlike the femoral artery and vein, the saphenous nerve does not pass through the adductor hiatus. The nerve emerges through the adductor canal and pierces the fascia lata between the tendons of the sartorius and gracilis muscles to become cutaneous. From here onwards, the saphenous nerve descends along the medial side of the leg, along with the great saphenous vein.
Branches
As the saphenous nerve leaves the adductor canal (and prior to piercing the deep fascia lata), it gives off an infrapatellar branch to contribute to the peripatellar plexus of nerves. Distally, the saphenous nerve gives off medial crural cutaneous branches to the skin and provides a communicating branch to connect with the medial branch of the superficial fibular nerve. An additional communicating branch is given off to the subsartorial plexus in the middle thigh.
Supplied Structures
The saphenous nerve provides sensory cutaneous innervation to the prepatellar skin and the skin over the medial leg, ankle, and foot.
List of Clinical Correlates
—Entrapment neuropathy (compression in the adductor canal)
References
Romanoff, M. E., Cory, P. C., Jr., Kalenak, A., Keyser, G. C. and Marshall, W. K. (1989) 'Saphenous nerve entrapment at the adductor canal', Am J Sports Med, 17(4), pp. 478-81.