SAPHENOUS NERVE

• It approaches the femoral artery where this vessel passes beneath the sartorius.

• Lies in front of the artery, behind the aponeurotic covering of the adductor canal, as far as the opening in the lower part of the Adductor magnus.

• Here it diverges from the artery, and emerges from behind the lower edge of the aponeurotic covering of the canal. 

• It descends vertically along the medial side of the knee behind the sartorius, pierces the fascia lata, between the tendons of the Sartorius and Gracilis, and becomes subcutaneous.

• The nerve then passes along the tibial side of the leg, accompanied by the great saphenous vein, descends behind the medial border of the tibia, and, at the lower third of the leg.

Divides into two branches:

• one continues its course along the margin of the tibia, and ends at the ankle.

• the other passes in front of the ankle, and is distributed to the skin on the medial side of the foot, as far as the ball of the great toe, communicating with the medial branch of the superficial peroneal nerve.

• The saphenous nerve, about the middle of the thigh, gives off a branch which joins the subsartorial plexus.

• At the medial side of the knee it gives off a large infrapatellar branch, which pierces the sartorius and fascia lata, and is distributed to the skin in front of the patella.

• Below the knee, the branches of the saphenous nerve (medial crural cutaneous branches) are distributed to the skin of the front and medial side of the leg, communicating with the cutaneous branches of the femoral, or with filaments from the obturator nerve.

• Saphenous nerve may be damaged in front of the medial malleolus during venesection of long saphenous vein.

• Therefore, femoral nerve damage can cause sensory loss over the area of great saphenous vein in leg.