[Location] Localized in the supine position, on the lateral side of the abdomen, right below the free end of the eleventh rib. ( Fig.36 )
 
[Regional Anatomy] Skin→subcutaneous tissue→obilquus externus abdominis→obilquus intemus abdominis→transversus abdominis. Superficial layer, the lateral crural cutaneous branch of the prior branches of the tenth and eleventh thoracic nerves, the subordiantial ramus of thoracoepigastric vein; deep layer, the tenth and eleventh thoracic nerves, and the branches or the subordiantial ramus of the tenth and eleventh posterior intercostals arteries and veins.