The saphenous nerve in foot and ankle surgery: its variable anatomy and relevance.

Background: Several studies have raised doubt regarding the role of the saphenous nerve (SN) in the foot, and some authors omit the SN from ankle blocks. Our aim was to assess the SN anatomy with reference to foot and ankle surgery.

Methods: In 29 cadaveric feet the SN was traced to its termination. At the ankle, the distances from the SN to the tibialis anterior tendon (TAT) and the long saphenous vein (LSV) were recorded.

Results: In 24 specimens, a SN was present at the ankle, and in 19 specimens extended to the foot. The mean distances from the nerve to the TAT and LSV were 15 mm and 4mm respectively. The nerve reached the first metatarsal (MT) in 28% of specimens.

Conclusion: Although the SN anatomy is less extensive than previously described, it often reaches the first MT and therefore should routinely be included in ankle blocks for forefoot surgery.