1
.
| Rib XII |
2
.
| Rib XI |
3
.
| External oblique muscle (origin) |
4
.
| Costal cartilage X |
5
.
| Lateral cutaneous branch intercostal nerve XI |
6
.
| Posterior branches intercostal artery XI |
7
.
| Internal oblique muscle (covered by fascia) |
8
.
| Lateral cutaneous branch thoracic nerve XII (subcostal nerve) |
9
.
| Muscular branches thoracic nerve XII |
10
.
| External oblique muscle (cut across and reflected) |
11
.
| Latissimus dorsi muscle (cut across) |
12
.
| Thoracolumbar fascia |
13
.
| Dorsal branch thoracic nerve XII (lateral branch) |
14
.
| Aponeurosis of latissimus dorsi (in this specimen aponeurosis overlaps posterior border of external oblique muscle so that there is no lumbar triangle) |
15
.
| Iliac crest |
16
.
| Superior cluneal nerves |
17
.
| Gluteus medius muscle |