A comparison of sartorius versus quadriceps stimulation for femoral nerve block: a prospective randomized double-blind controlled trial.

Background: Femoral nerve block is widely used for regional anesthesia and analgesia in many lower limb operations. Peripheral nerve stimulation of the femoral nerve may elicit 1 of 2 responses: contraction of the sartorius muscle through stimulation of its muscular branch or contraction of the quadriceps muscle through stimulation of its respective muscular branches. Historically, a quadriceps response has been preferred.