KINES 262 Anterior Chest Muscles

Sternocleidomastoid

Sternocleidomastoid Action

Neck Flexion Contralateral rotation of head

Sternocleidomastoid Origin

Clavicular head - sternal end of clavicle.

Sternal Head - manubrium

Sternocleidomastoid Insertion

mastoid process

Sternocleidomastoid Innervation

CN XI & (C2-C3)

Scalenes (anterior, middle, posterior)

Scalenes action

*Elevates ribs

Flexion & lateral flexion of the neck, Contralateral rotation of head (anterior only).

*Ipsilateral rotation (mid & posterior)

Scalenes Origin

Transverse and costal processes C2-C7

Scalenes insertion

Superior surface of first 2 ribs

Scalenes innervation

Cervical Spinal Nerves

Subclavius

Subclavius action

*Depression

*Protraction

Subclavius origin

1st Rib

Subclavius insertion

Clavicle (inferior border)

Subclavius innervation

Nerve to Subclavius

(C5-C6)

Pectoralis Minor

Pectoralis Minor action

*Depression

*Protraction

*Downward rotation

*Elevates ribs

Pectoralis Minor origin

Ribs 3-5

Pectoralis Minor insertion

Coracoid process

Pectoralis Minor innervation

Medial Pectoral nerve (C8, T1)

Pectoralis Major

Pectoralis Major action

*Flexion of shoulder

*Adduction of shoulder

*Internal rotation of shoulder

Pectoralis Major origin

Ribs 2-6, Sternum, Infero-medial portion of clavicle

Pectoralis Major insertion

Greater tubercle & lateral lip of bicipital groove

Pectoralis Major innervation

Pectoral nerve (C5-T1)

Anterior Deltoid

Anterior Deltoid action

*Abduction of shoulder

*Flexion of shoulder

*Internal rotation of shoulder

Anterior Deltoid origin

Clavicle and scapula

Anterior Deltoid insertion

Deltoid tuberosity

Anterior Deltoid innervation

Axillary nerve (C5-C6)