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.
Semispinalis capitis muscle
Longissimus capitis muscle
Longissimus cervicis muscle
Posterior scalene muscle
Iliocostalis cervicis muscle
Serratus posterior superior muscle (cut off near costal attachments)
Longissimus thoracis muscle
Iliocostalis muscle
Rib VI
Semispinalis cervicis muscle
Interspinalis cervicis muscle
Spinous process vertebra C. VII (vertebra prominens)
Trapezius muscle
Semispinalis thoracis muscle (note muscular slips extending to longissimus muscle)
Dorsal branch of posterior intercostal artery V
Middle cutaneous branch of dorsal branch thoracic nerve V