The posterior scalene is one of the scalene muscles of the neck. It is the smallest and the deepest of the scalene muscles.
- Attachments: Originates from the posterior tubercles of the transverse processes of C5-C7 and attaches into the second rib.
- Function: Elevation of the second rib, and ipsilateral lateral flexion of the neck.
- Innervation: Anterior rami of C6-C8.
- Blood Supply: Ascending cervical branch of inferior thyroid artery