Splenius cervicis muscle

The splenius cervicis is part of the superficial layer of the intrinsic back muscles. It is one of the two muscles in this group, the other being the splenius capitis.

Summary

• origin: spinous processes of T3-T6
• insertion: transverse processes of C1-C3
• innervation: dorsal rami of the lower cervical spinal nerves
• action: extension, lateral flexion and rotation of the head

Gross anatomy

Origin

• spinous processes of T3-T6

Insertion

• transverse process of the atlas, tip of the transverse process of the axis, and posterior tubercle of the third cervical vertebrae

Relations

• deep to the serratus posterior superior, rhomboids (major and minor) and trapezius muscles
• superficial to erector spinae and lower semispinalis muscles

Blood supply 

• descending branch occipital artery
• deep cervical artery

Innervation

• lateral branches of lower cervical dorsal rami from the cervical plexus

Action

• rotates and flexes the upper cervical vertebra towards the same side when acting unilaterally
• extends the head when acting bilaterally