Back (Superficial, Intermediate, Deep)

Superior Trapezius (Upper)

Actions: Side bending, scapular elevation, & scapular upward rotation

Origin: Occipital protuberance, nuchal ligament, spinous process C7-T1

Insertion: Lateral 1/3 of clavicle & acromion process

Innervation: Spinal accessory nerve

Middle Trapezius

Actions: Scapular retraction

Origin: Spinous process C7-T3

Insertion: Spine of scapula

Innervation: Spinal accessory nerve

Inferior Trapezius (Lower)

Actions: Scapular depression

Origin: Spinous process T4-T12

Insertion: Spine of scapular

Innervation: Spinal accessory nerve

Levator Scapulae

Actions: Elevates & rotates scapula; lateral flexion of neck

Origin: Transverse process C1-C4 vertebrae

Insertion: Medial border of superior angle of scapula

Innervation: Dorsal scapular nerve

Rhomboid Major

Actions: Retracts scapula

Origin: Spinous process T2-T5 vertebrae

Insertion: Medial boarder of scapula

Innervation: Dorsal scapular nerve

Rhomboid Minor

Actions: Retracts scapula

Origin: Spinous process C7-T1 vertebrae

Insertion: Medial boarder of scapula

Innervation: Dorsal scapular nerve

Latissimus Dorsi

Actions: Extends, adducts & medially rotates humerus

Origin: Spinous process T7- sacrum, thoracolumbar fascia, iliac crest, & inferior ribs

Insertion: Intertubercular groove of humerus

Rev action: Raises body towards arms during climbing

Innervation: Thoracodorsal nerve.

Serratus Anterior

Actions: Scapular protraction, upward rotation of scapula, stabilize the scapula

Origin: Surface of the 1st-8th ribs

Insertion: Medial boarder of scapula

Innervation: Long thoracic nerve

Serratus Posterior Superior

Actions: Facilitate respiration & elevate the ribs

Origin: C7-T3 vertebrae spinous process & Nuchal ligament

Insertion: Upper boarder of 2nd-5th ribs

Innervation: Ventral rami of intercoastal nerves T1-T5

Serratus Posterior Inferior

Actions: Facilitate respiration & depress the ribs

Origin: T11-L2 vertebrae spinous process

Insertion: Lower boarder of 9th-12th ribs

Innervation: Ventral rami of intercoastal nerves T9-T12