Shoulder Joint, Scapular and Pectoral Regions OIAInn's

Pectoral Major m. Origin (2)

Clavicular head:

1. Clavicle

Sternocostal head:

1. Sternum

2. Superior 6 costal cartilages

Pectoral Major m. Insertion

Intertubercular sulcus of humerus

Pectoral Major m. Inn. (2)

Lateral and medial pectoral nn.

Pectoral Major m. Action

Adducts + MR shoulder + flexes shoulder

Pectoralis Minor m. Origin

3-5 ribs

Pectoralis Minor m. Insertion

Coracoid process of scapula

Pectoralis Minor m. Inn

Medial pectoral n.

Pectoralis Minor m. Action

Draws scapula inferiorly + anteriorly against thoracic wall

Subclavius m. Origin

Junction of 1st rib and costal cartilage

Subclavius m. Insertion

Inferior clavicle

Subclavius m. Inn.

Subclavian n.

Subclavius m. Action

Anchor + depress scapula

Serratus Anterior m. Origin

1-8 ribs

Serratus Anterior m. Insertion

Medial border of scapula

Serratus Anterior m. Inn.

Long thoracic n.

Serratus Anterior m. Action

1. Protract scapula

2. Hold scapula against the thoracic wall

3. Upwardly rotates scapula

Winged Scapula

Damage to long thoracic n. leads to paralysis of ipsilateral serratus anterior m.

- Medial scapula turns 90 degrees so that the medial border protrudes

Scapulohumeral mm.

Scapula to humerus (move the humerus)

Deltoid m. Origin (3)

1. Clavicle

2. Acromion

3. Spine of scapula

Deltoid m. Insertion

Deltoid tuberosity of humerus

Deltoid m. Inn.

Axillary n.

Deltoid m. Actions

Anterior: Flex + MR shoulder

Middle : Abduct shoulder

Posterior: Extend + LR shoulder

Teres Major m. Origin (2)

1. Inferior lateral border of scapula

2. Posterior surface of inferior angle of scapula

Teres Major m. Insertion

Intertubercular sulcus of humerus

Teres Major m. Inn.

Lower subscapular n.

Teres Major m. Actions (2)

Adduct + MR shoulder

Supraspinatus m. Origin

Supraspinous fossa of scapula

Supraspinatus m. Insertion

Superior facet of greater tubercle of humerus

Supraspinatus m. Inn.

Suprascapular n.

Supraspinatus m. Action

Initiates + assists deltoid in shoulder abduction

Infraspinatus m. Origin

Infraspinatus fossa of scapula

Infraspinatus m. Insertion

Middle facet of greater tubercle of humerus

Infraspinatus m. Inn.

Suprascapular n.

Infraspinatus m. Action

LR shoulder

Teres Minor m. Origin

Middle part of lateral border of scapula

Teres Minor m. Insertion

Inferior facet of greater tubercle of humerus

Teres Minor m. Inn.

Axillary n.

Teres Minor m. Action

LR shoulder

Subscapularis m. Origin

Subscapular fossa

Subscapularis m. Insertion

Lesser tubercle of humerus

Subscapularis m. Inn. (2)

Upper and lower subscapular nn.

Subscapularis m. Actions

MR + adducts shoulder