Semispinalis Thoracis
Back
Deep thoracic spine extensor — the most caudal part of the semispinalis group, typically spanning 5-6 vertebral segments.
Function
Extends and contralaterally rotates thoracic/cervical spine
Origin
Transverse processes T6-T10
Insertion
Spinous processes C6-T4
Innervation
Posterior rami of spinal nerves