The abdominal cutaneous nerve entrapment syndrome.

Entrapment of the abdominal segmental nerves within the rectus abdominis muscle may produce abdominal pain simulating surgical or genito-urinary disease. The diagnosis can be made by localising with one finger an area of tenderness close to the lateral border of the muscle. Pressure at this site will usually reproduce the pain and precise injection of local anaesthetic will abolish the pain immediately. Effective long-term relief is usually obtained by the injection of long acting steroid or a small volume of 7 percent aqueous phenol.