Dissection of thoracic and lumbosacral regions of back from a posterior approach

Components of erector spinae muscle in relation to semispinalis muscles in upper thoracic region

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Image #213-6

Dissection of thoracic and lumbosacral regions of back from a posterior approach

Components of erector spinae muscle in relation to semispinalis muscles in upper thoracic region

This close-up view of the back of the thorax and lower part of the neck shows in more detail the relations of the iliocostalis, longissimus and spinalis muscles illustrated in the previous photograph. In addition, the semispinalis group of muscles (1, 10, 14) has been partially exposed and it can be seen that there is a close interrelation between this group and the longissimus and spinalis muscles.

1. Semispinalis capitis muscle
2. Longissimus capitis muscle
3. Longissimus cervicis muscle
4. Posterior scalene muscle
5. Iliocostalis cervicis muscle
6. Serratus posterior superior muscle (cut off near costal attachments)
7. Longissimus thoracis muscle
8. Iliocostalis muscle
9. Rib VI
10. Semispinalis cervicis muscle
11. Interspinalis cervicis muscle
12. Spinous process vertebra C. VII (vertebra prominens)
13. Trapezius muscle
14. Semispinalis thoracis muscle (note muscular slips extending to longissimus muscle)
15. Dorsal branch of posterior intercostal artery V
16. Middle cutaneous branch of dorsal branch thoracic nerve V
17. Spinalis thoracis muscle