3 – The axial anatomy of the deep cervical plexus block

At the level of the transverse process of vertebral body C6, both the anterior and middle scalene muscles are prominent, while the capitis longus muscle is inconspicous and located just lateral to the colli longus muscle

The anterior scalene muscle is attached to the anterior tubercles and the middle scalene muscle to the posterior tubercles of the transverse processes

At the level of the transverse process of vertebral body C4, the anterior scalene muscle has tapered while the cross section of the capitis longus muscle has become more prominent; the sympathetic trunk runs anterior to the capitis longus muscle

The picture on the right shows an axial view at the level of vertebral body C6 with the C5 and C6 cervical spinal nerve roots (magenta and green dots in upper picture) and C4 with the C3 and C4 roots (white and yellow dots in lower picture)