Anterior abdominal wall
| Muscle | Action | Origin | Insertion | Innervation |
|---|---|---|---|---|
| External oblique | Flexion of trunk | Outer surfaces of ribs 5-12 | Lateral lip of iliac crest Aponeurosis ending in linea alba |
Anterior rami of T7-T12 |
| Internal oblique | Flexion of trunk | Thoracolumbar fascia Lateral 2/3 inguinal ligament Iliac crest |
Inferior border of lower 3-4 ribs Aponeurosis ending in linea alba Pubic crest Pectineal line |
Anterior rami T7-L1 |
| Transversus abdominis | Compress abdominal contents | Ribs 4-10 costal cartilages Thoracolumbar fascia Iliac crest Lateral ⅓ inguinal ligament |
Aponeurosis ending in linea alba Pubic crest Pectineal line |
Anterior rami T7-L1 |
| Rectus abdominis | Compress abdominal contents; flex vertebral column; tense abdominal wall | Pubic crest, pubic tubercle, pubic symphysis | Costal cartilages ribs 5-12 | Anterior rami T7-T12 |