Shoulder region Bones Joints Muscles Vessels & Nerves

Classifications of muscles that move the shoulder A. muscles connecting scapula to humerus B. muscles connecting trunk to scapula C. muscles connecting trunk to humerus

Biceps & Triceps tendons

A. muscles connecting scapula to humerus 1.Supraspinatus 2.Infraspinatus 3.Teres minor 4.Subscapularis 5.Teres major 6.Coracobrachialis 7.Deltoid

Short muscles

Function: abduction

Subscapularis Function: Int. rotation

Rotator Cuff

Rotator cuff function: only 25% of the humeral head is in contact with the glenoid fossa. The rotator cuff muscles compress and depress the humeral head within the glenoid fossa.

Rotator Cuff Disease photo

Quiz supraspinatus supraspinatus subscapularis infraspinatus teres minor teres minor

Teres major Function: adduction of humerus med rotator Why medial? Origin: – Inf angle of scapula Insertion: – Med lip of groove Actions: – Internal rotation and adduction of arm

Coracobrachialis Function: flex & adduct the shoulder joint

Deltoid Origin: – Clavicle, scapula Insertion: – Deltoid tuberosity of humerus Actions: – Abduction – Anterior deltoid: internal rotation – Posterior deltoid: external rotation

Classifications of muscles that move the shoulder A. muscles connecting scapula to humerus B. muscles connecting trunk to scapula C. muscles connecting trunk to humerus

B. muscles connecting trunk to scapula 1.Serratus anterior 2.Levator scapula 3.Rhomboid major 4.Rhomboid minor 5.Trapezius 6.Pectoralis minor

Serratus Anterior Origin: – Ribs Insertion: – Medial border of scapula Actions: – Protraction and rotation of scapula

Winged scapula

Levator scapula Origin: – Cervical vertebrae Insertion: – Scapula Action: – Elevation of the scapula

Rhomboid major and minor Origin: – Cervical and Thoracic vertebrae Insertion: – Scapula Actions: – Retraction – Elevation

Trapezius Origin: – Occipital bone of skull, cervical and thoracic vertebrae Insertion: – Clavicle and Scapula Actions: – Elevation – retraction

Pectoralis Minor Origin: – Ribs Insertion: – Coracoid process of scapula Action: – Depression of scapula

Depression of scapula

Classifications of muscles that move the shoulder A. muscles connecting scapula to humerus B. muscles connecting trunk to scapula C. muscles connecting trunk to humerus

Pectoralis major Latissimus dorsi

Pectoralis Major Origin: – Clavicle, sternum, upper ribs Insertion: – Crest of greater tubercle and lat lip Action: – Add, med rotation

Latissimus Dorsi Origin: – Vertebrae, sacrum, ilium Insertion: – Medial lip Actions: – Adduction and med rotation of humerus

Latissimus Dorsi if humerus is fixed

Covering th front and back of the trunk. The pectoralis major and latissimus dorsi both adduct and medially rotate the Humerus. Lower edge of the pectoralis major muscle on rib 7 = upper edge of the latissimus dorsi on vertebra T7.

Shoulder Girdle Movements