[Inguinal Approach in Obturator Nerve Block]

The most commonly utilized approaches to obtura- tor nerve block are the pubic approach and the inter- adductor approach. However, the pubic approach is difficult and extremely invasive because a needle must be inserted into the pelvis and there have been some cases of vascular puncture using the pubic approach. Moreover, some cases accompanied clinical signs of local anesthetic toxicity using both approaches. Thus, we devised and performed the inguinal approach, where the femoral artery and vein are shifted outward in the level of the inguinal crease and the needle is inserted vertically from the innerside of them using electric stimulation. However, we experienced some unsuccessful cases due to a single branch block, be- cause the obturator nerve is separated into the ante- rior and posterior branches at the level of the inguinal crease. Choquet reported a new inguinal approach that blocks both branches which is easy and useful because the frequency of the needle insertion is less ; the block performance time is shorter ; the success rate is higher ; and the pain and discomfort are less than that with the pubic approach.