Saphenous Nerve Block Technique With Neurostimulation

To the Editor: Many approaches to the saphenous nerve block have been described.1 Because this is a sensory nerve, most techniques that have been described use anatomical landmarks as guides to determine the site of local anesthetic injection.2,3 For many other peripheral nerve blocks, neurostimulation is commonly used to identify injection sites by eliciting the distinct motor response of the particular nerve stimulated. In the saphenous nerve block method described here, neurostimulation is also employed. However, the identifying feature is not a motor response, but rather a paresthesia best described as a “tapping” felt by the patient on the medial aspect of the ankle or lower leg. At our institution this method of saphenous nerve blockade is routinely used in conjunction with the popliteal sciatic nerve block. The patient is placed in the prone position. Both regions to be blocked are prepped to allow for use of the same stimulating needle. The prep for the saphenous nerve block involves the medial aspect of the knee, including the distal aspect of the sartorius muscle and the region of the medial epicondyle of the femur. Local anesthetic is injected subcutaneously to anesthetize the skin for