Shoulder Joint

Articulation of the head of the humerus with the glenoid fossa of the scapula

Glenohumeral Joint

Deepens the fossa and cushions against impact of humeral head in forceful movements

Glenoid labrum

What type of joint is the glenohumeral joint?

Ball and socket joint

What is the most mobile joint in the human body?

Glenohumeral joint

The glenohumeral articulation is stabilized by which two types of tissues?

Ligaments and muscles

Ligamentous reinforcements of the glenohumeral joint

Coracohumeral, glenohumeral, and coracoacromial ligaments

Movements of the glenohumeral joint

Flexion, extension, and hyperextension
Circumduction
Abduction, Adduction
Inward (medial), outward (lateral) rotation

Anterior muscles of the shoulder joint

Pectoralis major, coracobrachialis, subscapularis, biceps brachii

Posterior muscles of the shoulder joint

Infraspinatus, teres minor

Superior muscles of the shoulder joint

Deltoid, supraspinatus

Inferior muscles of the shoulder joint

Latissimus dorsi, teres major, long head of triceps brachii

The clavicular portion of the pectoralis major contributes to what movements of the humerus?

Flexion, horizontal adduction, and medial rotation

The sternocostal portion of the pectoralis major contributes to what movements of the humerus?

Extension and medial rotation with adduction

The ______________ is responsible for adduction of the glenohumeral joint

Coracobrachialis

What muscle functions to stabilize the shoulder joint along with the deltoid and long head of the triceps?

Coracobrachialis

The _______________ is responsible for internal/medial rotation of the humerus

Subscapularis

The ________________ functions in flexion of the glenohumeral joint

Biceps brachii

________________ is a powerful abductor of the humerus

Deltoid

Which part of the deltoid is responsible for abduction of the glenohumeral joint

Middle

Which part of the deltoid is responsible for abduction & all forward movements of the arm (flexion), and medial rotation

Anterior

What part of the deltoid is responsible for abduction, horizontal & diagonal abduction

Posterior

Which two muscles work together to facilitate abduction of the arm?

Supraspinatus and deltoid

Which two muscles are responsible for lateral/external rotation of the arm?

Infraspinatus and teres minor

The latissimus dorsi functions in what movements of the arm?

Extension, adduction & internal rotation

The teres major functions in what movements of the arm?

Medial rotation, extension, and adduction

The triceps brachii functions in what movements of the humerus?

Adduction, extension, and hyperextension

What is the glenohumeral joint stabilized by?

The rotator cuff

What four muscles make up the rotator cuff?

Supraspinatus, infraspinatus, teres minor, and subscapularis

When the glenohumeral joint performs abduction, what is the corresponding movement of the shoulder girdle?

Upward rotation of the scapula

When the glenohumeral joint performs adduction, what is the corresponding movement of the shoulder girdle?

Downward rotation of the scapula

When the glenohumeral joint performs flexion, what is the corresponding movement of the shoulder girdle?

Posterior tilt, abduction, upward rotation, and lateral tilt of the scapula

When the glenohumeral joint performs extension, what is the corresponding movement of the shoulder girdle?

Downward rotation of the scapula, adduction, and medial tilt

When the glenohumeral joint performs hyperextension, what is the corresponding movement of the shoulder girdle?

Anterior tilt of the scapula

When the glenohumeral joint performs lateral rotation, what is the corresponding movement of the shoulder girdle?

Adduction and medial tilt of the scapula

When the glenohumeral joint performs medial rotation, what is the corresponding movement of the shoulder girdle?

Abduction & lateral tilt of the scapula

When the glenohumeral joint performs horizontal adduction, what is the corresponding movement of the shoulder girdle?

Abduction of the scapula

When the glenohumeral joint performs horizontal abduction, what is the corresponding movement of the shoulder girdle?

Adduction of the scapula

When the glenohumeral joint performs diagonal abduction, what is the corresponding movement of the shoulder girdle?

Adduction of the scapula

When the glenohumeral joint performs diagonal adduction, what is the corresponding movement of the shoulder girdle?

Abduction of the scapula

MOI: Arm is forcefully abducted and laterally rotated
PATH: Head of humerus is forced out of the glenoid fossa
S&S: Arm held out from side in a position of slight abduction and lateral rotation

Dislocation of the shoulder

MOI: Overuse / Falling on an outstretched hand
PATH: Supraspinatus most often injured
S&S: Pain, inflammation, weakness

Rotator cuff strains