Abstract:

Objective To investigate the intramuscular nerve distribution pattern of anterolateral abdominal wall muscles and to explore its clinical significance. Methods Twenty-four anterolateral abdominal wall muscles from twelve Chinese adult cadavers that were fixed with formaldehyde were removed for modified Sihler’s staining. Results Most of the innervation of the anterolateral abdominal wall muscles originated from the segmental distribution of the intercostal nerve. Each muscular serration of the obliquus externus abdominis muscle had an independent innervation and there was a single longitudinal nerve dense band above the iliac crest between the anterior superior iliac spine and iliac tubercle. In the obliquus internus abdominis muscle, there was a longitudinal nerve dense band above the midpoint of the inguinal ligament and a transverse nerve dense band above the iliac crest. In the transversus abdominis muscle, there was an arched nerve dense band between the anterior superior iliac spine and the junction of the ninth and eighth costal cartilage. The rectus abdominis muscle had one transverse nerve dense band in the middle of each muscle belly and the upper 3 muscle bellies had independent innervation. Conclusion The obliquus externus abdominis and rectus abdominis muscle can be divided into neuromuscular subdivisions. The nerve dense zone in each muscle should be considered as the optimal target site for botulinum toxin A injections and local anesthesia, and it should not be designed as the incision site for abdominal wall surgery.

Key words: Anterolateral abdominal wall muscle, Intramuscular nerve, Distribution pattern, Sihler’s staining, Applied anatomy, Human