Action.

Muscle.

Origin.

Insertion.

Nerve-supply.

Elevation

Trapezius (upper fibres)

Inner third superior curved line of occipital bone and external occipital protuberance from the ligamentum nuchae, the spine and supraspinous 1iga-ments of the seventh cervical, and all the thoracic vertebrae

Outer third of the posterior surface of the clavicle ; inner border of the acromion process, and the upper border of the spine of the scapula, and the rough triangular surface at the base of the spine

Spinal accessory and nerves from the cervical plexus

Levator anguli scapulae

Posterior tubercles of the transverse processes of the upper cervical vertebrae between scalenus medius and splenius colli

The upper fourth of the vertebral border of the scapula from the spine to the angle

Cervical plexus ; posterior scapular

Rhomboideus major

Spines of the thoracic vertebrae, second to fifth inclusive

The vertebral border of the scapula from the spine to the lower angle to a membranous band attached by the extremities

Posterior scapular

Elevation

Rhomboideus minor

Spines of seventh cervical and first thoracic vertebrae

The vertebral border of the scapula opposite the base of the spine

Posterior scapular

Sterno-mastoid

A narrow head from the anterior surface of sternum, and also from inner third of upper surface of clavicle

Outer surface of mastoid process, and the outer half of the superior curved line of the occipital bone

Spinal accessory and cervical plexus

Depression

Trapezius (lower fibres)

See Elevation

Subclavius

Upper surface of first costal cartilage

Middle third of under surface of clavicle

Brachial plexus

Pectoralis minor

From the anterior part of upper border of third, fourth, and fifth ribs and fascia covering them

Outer half of upper surface of coracoid process

External and internal anterior thoracic

Latissimus dorsi

From the spines of the lower six thoracic, and of all the lumbar vertebrae; the posterior part of the iliac crest, slips from the lower four ribs and the inferior angle of the scapula; and deep fascia covering back

The floor of the bicipital groove on the humerus

Third sub scapular

Pectoralis major (lower fibres)

From the inner half of the anterior surface of the clavicle; from half the anterior surface of the sternum in its whole length; and from the cai'tilages of the upper six ribs

The outer lip of the bicipital groove on the humerus

External and internal anterior thoracic

Forwards

Serratus magnus

From outer aspect of upper eight or nine ribs

The ventral surface of the vertebral border of the scapula in its whole length

Posterior thoracic

Pectoralis major

See Depression

Pectoralis minor

See. Depression

Back-wards

Trapezius

See Depression

Rhomboids

See Elevation

Latissimus dorsi

See Depression