Levator Scapulae

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Function

Main function is to elevate and retract the shoulder girdle at the scapulothoracic joint. At the same time, it helps in preventing the depression of the girdle when carrying heavy loads. Additionally, the muscle participates in the stabilization of the scapula and the inferior rotation of the glenoid cavity.

Relations

-Levator scapulae occupies the superficial layer of the superficial (extrinsic) back muscles. -Upper part of the muscle lies underneath the splenius capitis and SCM muscles, while its lower part is covered by trapezius. -Only the middle part of the levator scapulae remains uncovered. For that reason, the muscle can be most easily palpated in this area. In addition, the middle part helps to form the floor of the posterior triangle of the neck.

Innervation

Anterior rami of the nerves C3 and C4, dorsal scapular nerve (branch of the C5)

Insertion

Medial border of scapula (from superior angle to root of spine of scapula)

Actions

Scapulothoracic joint: Draws scapula superomedially, rotates glenoid cavity inferiorly Cervical joints: Lateral flexion of neck (ipsilateral), extension of the neck

Origin

Transverse processes of vertebrae C1-C4

Levator Scapulae

-Long and slender muscle that anatomically belongs to the superficial layer of extrinsic muscles of the back. Functionally, however, it is considered to be a muscle of scapular motion along with the rhomboids, serratus anterior, serratus posterior superior and inferior muscles. -Extends from the transverse processes of vertebrae C1-C4 to the medial border of scapula. -As its name suggests, the main function of this muscle is to elevate the scapula. Additionally, it acts with the trapezius, latissimus dorsi, rhomboids, pectoralis major and pectoralis minor muscles to inferiorly rotate the glenoid cavity, stabilize the spine, and extend and laterally flex the neck.

Blood supply

-Transverse cervical and ascending cervical arteries (branches of the thyrocervical trunk) -Vertebral portion of the muscle is supplied by the vertebral artery.

Clinical notes

An isolated lesion of the dorsal scapular nerve with a consequent paralysis of the levator is very rare. The symptoms include "winging" of the scapula (scapula alata), as well as atrophy of both the levator and rhomboid muscles. As the affected patients may have no clear complaints, the correct diagnosis is often made too late. One muscle of the human body which is prone to stiffening and chronic pain due to false posture in everyday life. Common causes include carrying heavy shoulder bags, permanent lifting of the shoulders while sitting at a desk and sleeping on one side of the body without proper head support.


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