Muscles of the Anterior Abdominal Wall

Muscles of the Anterior Abdominal Wall Muscle Origin Insertion NerveAction External oblique External surface of lower eight ribs Anterior half of iliac crest; anterior-superior iliac spine; pubic tubercle; linea alba Intercostal; subcostal n. Compresses abdomen; flexes trunk; active in forced expiration Internal oblique Lateral two thirds of inguinal ligament; iliac crest; thoracolumbar fascia Lower four costal cartilages; linea alba; pubic crest; pectineal line Intercostal n.; subcostal; iliohypogastric and ilioinguinal nn. Compresses abdomen; flexes trunk; active in forced expiration Transverse Lateral one third of inguinal ligament; iliac crest; thoracolumbar fascia; lower six costal cartilages Linea alba; pubic crest; pectineal line Intercostal ; subcostal iliohypogastric and ilioinguinal nn. Compresses abdomen; depresses ribs Rectus abdominis Pubic crest and pubic symphysis Xiphoid process and costal cartilages Intercostal ; subcostal n. Depresses ribs; flexes trunk Pyramidal Pubic body Linea alba Subcostal Tenses linea alba Cremaster Middle of inguinal ligament; lower margin of internal oblique muscle Pubic tubercle and crest Genitofemoral Retracts testis ◄.....Go back to the Gross Anatomy homepage