Partial denervation of the hip has been performed for the relief of pain in various types of chronic arthritis of the hip. This operation consists of an intrapelvic obturator neurotomy and section of the nerve to the quadratus femoris. It is relatively easy to perform and produces no constitutional reaction, so that it. is applicable to a large group of patients. Of forty-two patients with painful arthritis of the hip who were thus treated, satisfactory relief from pain was obtained in twenty-eight. The longest postoperative observation period was twenty months. When obturator neurotomy alone was used for the relief pain, it was found that the intrapelvic approach was more effective than the extrapelvic operation. Eleven of the fourteen failures in this series were treated by extrapelvic obturator-nerve section. Lack of consistently satisfactory results may be attributed to anatomical variations in the sensory nerve supply to the hip.