Levator scapulae muscle
The levator scapulae is a long muscle of the back lying in the second layer below the most superficial back muscles and on the side of the neck. It may also be considered as a muscle of the shoulder. Its main action is lifting the scapula.
The upper part of this muscle lies beneath the splenius capitis and sternocleidomastoid muscle, while its lower part is located below the trapezius. The middle part is the only portion of the muscle uncovered by other muscles in the lateral neck region, where the muscle is therefore easily palpable.
- Origin: transverse processes of the atlas (C1) and axis (C2), as well as from the posterior tubercles of the third and fourth cervical vertebrae (C3, C4).
- Insertion: posterior surface of the medial scapular border - from the superior angle to the root of the spine of the scapula.
- Action: elevates the scapula.
- Innervation: branches of the third and fourth cervical spinal nerves (C3, C4), and also the dorsal scapular nerve, which arises from the fifth cervical spinal nerve (C5).