Regional Distribution of the Saphenous Nerve below the Adductor Canal: An Anatomical Study

The adductor canal is an aponeurotic tunnel that courses between the anterior and medial compartments in the middle third of the thigh. The canal begins at the apex of the femoral triangle and extends to the adductor hiatus. Its major contents are the superficial femoral artery, the nerve to vastus medialis, and the saphenous nerve. The latter two nerves are branches of the posterior division of the femoral nerve. Along with the medial and intermediate cutaneous nerves of the thigh and the lateral femoral cutaneous nerve the saphenous nerve contributes to the sensory distribution around the anterior aspect of the knee. This anatomic cadaveric study defined the course of the saphenous nerve and its divisions along the medial aspect of the knee. Landmark-based distance measurements were recorded in reference to the proximal border of the patella, medial border of the patella, medial epicondyle, medial femoral condyle, and posterior femoral condyle. The clinical implications of our findings suggest there is opportunity to obtain medial sensory analgesia during total knee arthroplasty when periarticular injections of bupivacaine derived medications are injected in the region of saphenous nerve proximal and posterior to the medial femoral condyle.