Transfer of two motor branches of the anterior obturator nerve to the motor portion of the femoral nerve: an anatomical feasibility study.

Femoral nerve lesions are uncommon, but very distressing at the functional level because of the absence of knee locking mechanism by the quadriceps muscle. We propose here a new neurotization procedure of obturator nerve motor branches to the motor portion of the femoral nerve in the thigh. This study was conducted on five cadavers. The motor portion of the femoral nerve and the motor branches of the obturator nerve, supplying the gracilis and adductor longus muscles, were isolated. The distance between nerve endings and diameter were measured to determine if a direct neurorrhaphy was possible between the femoral nerve and the two united branches of the obturator nerve. The overlap between the two nerve endings was 26 mm on average, and the mean diameter of the two nerve endings was 3.6 mm for the united branches of the obturator nerve and 3.7 mm for the femoral nerve. Thus, a direct suture was possible in all cases. In this anatomical study, access to the femoral nerve and two united branches of the obturator nerve was easy, in contrast to transfer in the pelvis. Moreover, direct suture without tension was possible in all cases. Thus, this transfer is simple and perfectly reproducible and may have a clinical application in proximal femoral nerve injuries.