Purpose: Abdominal wall nerve injury as a result of trocar placement for laparoscopic surgery is rare. We intend to discuss causes of abdominal wall paresis as well as relevant anatomy.
Methods: A review of the nerve supply of the abdominal wall is illustrated with a rare case of a patient presenting with paresis of the internal oblique muscle due to a trocar lesion of the right iliohypogastric nerve after laparoscopic appendectomy.
Results: Trocar placement in the upper lateral abdomen can damage the subcostal nerve (Th12), caudal intercostal nerves (Th7-11) and ventral rami of the thoracic nerves (Th7-12). Trocar placement in the lower abdomen can damage the ilioinguinal (L1 or L2) and iliohypogastric nerves (Th12-L1). Pareses of abdominal muscles due to trocar placement are rare due to overlap in innervation and relatively small sizes of trocar incisions.
Conclusion: Knowledge of the anatomy of the abdominal wall is mandatory in order to avoid the injury of important structures during trocar placement.