Anatomical Variations of the Saphenous Nerve in the Adductor Canal

Local anaesthetic blockage of the saphenous nervewithin the adductorcanal block hasevolved asa popular analgesic technique for operations around the knee. However, not all patients benefit equally, despite accurate placement of local anaesthetic into the adductor canal under ultrasound guidance. It has been proposedthat anatomical variations of the saphenous nerve within the canal may account for the variable clinical efficacy of such blocks. Thus, we performed a dissection study of 22 cadaveric knees to determine the variance of the saphenous nerve.This study revealed multiple variations of the saphenous nerve within the adductor canal. However, despite these anatomical variations, an accurately placed adductor canal block should provide adequate anaesthesia of the saphenous nerve and its branches.