Proximal upper limb muscles LECTURE

3 joints of the shoulder girdle

1. sternoclavicular

2. acromioclavicular

3. glenohumeral

1 articulation of the shoulder girdle

Scapulothoracic articulation

What type of joint is the sternoclavicular joint?

Saddle, multiaxial

What type of joint is the acromioclavicular joint?

Plane, multiaxial

Ligaments of the acromioclavicular joint (2)

1. Coracoclavicular ligament

2. Coracoacromial ligament

3 joints in the elbow

1. humeroulnar

2. humeroradial

3. proximal radioulnar

What type of joint is the humeroulnar joint?

Hinge, uniaxial

What type of joint is the radiohumeral joint?

Pivot, uniaxial

What type of joint is the radioulnar joint?

Pivot, uniaxial

Important ligaments of the elbow

Ligaments:

1. radial collateral ligament

2. annular ligament of radius

3. ulnar collateral ligament:

   1. anterior band (cord-like)

   2. posterior band (fan-like)

   3. oblique band

Anterior axioappendicular muscles (3)

1. Pectoralis major

   1. sternal head

   2. clavicular head

2. pectoralis minor

3. serratus anterior

Posterior axioappendicular muscles (4)

1. Trapezius

   1. upper (descending)

   2. middle

   3. lower (ascending)

2. Rhomboid

   1. major

   2. minor

3. Teres major

4. Latissimus dorsi

What makes up the anterior and posterior axillary fold?

Anterior: pectoralis major

Posterior: latissimus dorsi + teres major

3 parts of deltoid muscle

1. anterior

2. middle

3. posterior

4 rotator cuff muscles

1. subscapularis

2. supraspinatus

3. infraspinatus

4. teres minor

Anterior arm muscles (3)

1. biceps brachii

   1. short head

   2. long head

2. coracobrachialis

3. brachialis

Posterior arm muscle (1)

Triceps brachii:

1. lateral

2. long

3. medial

What muscles are involved in glenohumeral flexion?

1. anterior deltoid

2. coracobrachialis

3. pectoralis major (clavicular head)

What muscles are involved in glenohumeral extension?

1. posterior deltoid

2. latissimus dorsi

3. teres major

What muscles are involved in glenohumeral abduction?

1. middle deltoid

2. supraspinatus for first 15°

What muscles are involved in glenohumeral adduction?

1. latissimus dorsi

2. pectoralis major

3. teres major

What muscles are involved in glenohumeral internal rotation?

1. subscapularis

2. pectoralis major

3. latissimus dorsi

4. teres major

What muscles are involved in glenohumeral external rotation?

1. infraspinatus

2. teres minor

Muscles involved in scapulothoracic elevation?

1. trapezius

2. levator scapulae

Muscles involved in scapulothoracic depression?

1. serratus anterior

2. latissimus dorsi

Muscles involved in scapulothoracic protraction?

1. serratus anterior

2. pectoralis major (sternocostal head)

Muscles involved in scapular retraction?

1. rhomboids

2. trapezius

3. latissimus dorsi

Muscles involved in scapular upwards rotation?

1. trapezius

2. serratus anterior

Muscles involved in scapular downward rotation?

1. rhomboids

2. latissimus dorsi

3. levator scapulae

4. pectoralis minor

5. pectoralis major (sternocostal head)

Muscles involved in elbow flexion (and their specific role)

1. biceps brachii (supination)

2. brachialis (any forearm position)

3. brachioradialis (neutral forearm)

Muscles involved in elbow extension

Triceps brachii

Forearm compartments

Anterior: flexor-pronator

Posterior: extensor-supinator

Anterior superficial muscles of forearm (from lateral to medial)

1. pronator teres

2. flexi carpi radialis

3. palmaris longus

4. flexi carpi ulnaris

Anterior intermediate muscles of forearm

Flexor digitorum superficialis

Anterior deep muscles of the forearm (from lateral to medial)

1. flexor digitorum profundus

2. flexor pollicis longus

3. pronator quadratus

Posterior superficial muscles of the forearm (radial side)

1. brachioradialis

2. extensor carpi radialis longus

3. extensor carpi radialis brevis

4. abductor pollicis longus

5. extensor pollicis brevis

Posterior superficial muscles of the forearm (mid and ulnar side)

1. extensor digitorum

2. extensor digiti minimi

3. extensor carpi ulnaris

Posterior deep muscles of forearm

1. supinator

2. abductor pollicis longus

3. extensor pollicis brevis

4. extensor pollicis longus

5. extensor indicis

6 posterior synovial sheaths

1. extensor carpi ulnaris

2. extensor digiti minimi

3. extensor digitorum and extensor indicis

4. extensor pollicis longus

5. extensor carpi radialis longus and extensor carpi radialis brevis

6. abductor pollicis longus and extensor pollicis brevis

Anatomical snuff box

Floor of snuff box: scaphoid bone, radial artery

Borders of snuff box: extensor pollicis brevis (thumb side) extensor pollicis longus (middle of hand side0

Muscles involved in pronation

1. pronator teres

2. pronator quadratus

Muscles involved in supination

1. biceps brachii

2. supinator

Muscles involved in wrist flexion and extension

Flexion:

• flexor carpi radialis

• flexor carpi ulnaris

Extension:

• extensor carpi radialis longus

• extensor carpi radialis brevis

• extensor carpi ulnaris

Muscles involved in extrinsic finger flexion

Flexes all joints that the tendon crosses

1. flexor digitorum superficialis

2. flexor digitorum profundus

Primarily flexes PIP joint

Muscles involved in extrinsic thumb flexion, extension and abduction

• flexor pollicis longus

• extensor pollicis brevis

• extensor pollicis longus

• abductor pollicis longus

Extrinsic finger extensors

1. extensor digitorum

2. extensor indicis

3. extensor digiti minimi