MUSCLES OF THE UPPER ARM

The dorsal muscles of the shoulder are:

1. Infraspinatus muscle.

2. Teres Minor

3. Teres major

4. subscapularis

5. Lattissimus dorsi

Which muscles are the rotator cuff muscles?

Acronym is SITS

S- supraspinatus muscle

I- Infraspinatus muscle

T- Teres Minor muscle

S-Subscapularis muscle

NOTE: The head of all rotator cuff muscles insert/attach to the proximal end of the humerus.

Infraspinatus muscle

origin: infraspinous fossa

Insertion: Gretare tubercle of the Humerus

Function: aids in lateral roatation

Teres minor muscle

Origin: infrasonic fossa and lateral border of the scapula

Insertion: greater tubercle of the humerus.

Function: shoulder joint; lateral rotation, adduction in the scapular plane

Subscapularis muscle

Origin: from the subscapular fossa of the scapula.

Insertion: lesser tubercle of the humerus.

Function: shoulder joint; medial rotation

Supraspinatus muscle

Origin: supraspinaous fossa

Insertion: greater tubercle of the humerus.

Latissimus Dorsi

Origin: spinous process of the six lower thoracic vertebrae and the lumbar vertebrael

Insertion:crest of lesser tubercle

function: shoulder joint adduction, medial rotation, retroversion

Bicep Brachii

Origin: long head: supraglenoid tubercle

short head: tip of the coracoid process

Insertion: the two heads of the biceps continue distal and inserts on the radial tuberosity.

Coracobrachilis muscle

Origin: coracoid process of the scapula

Insertion: anterior surface of the humerus medial and distal to the crest of lesser tubercle

Function: F: shoulder joint: medial rotation, adduction, Elevation

Branchii

Origin: anterior surface of the humerus (lower half)

Insertion: tuberosity of ulna

Function: elbow joint: flexion, tenses the joint capsule

Dorsal muscles of the upper arm

1. Triceps Brachii.

2. Aconeus muscle

Triceps brachii

Origin: long head: infraglenoid tubercle

medial head: posterior surface of the humerus medial and distal of the radial groove

lateral head: posterior surface of the humerus lateral and proximal of the radial groove

Insertion: Olecranon process of the ulna

Function: shoulder joint: long head: adduction, retroversion elbow joint:

extension (most important muscle

Anconeus Muscle

Origin: lateral epicondyle of humerus

Insertion: posterior surface of the uina, olecranon.

Function: elbow joint: extension

Ventral superficial muscles of the forearm.

1. Pronator teres

2. Flexor carpi radialis

3. Palmaris longus

4. Flexor digitorum superficialis

5. Flexor carpi ulnaris

Pronator teres

Flexor carpi radialis

Palmaris longus

Flexor digitorum superficialis

Flexor carpi ulnaris

Ventral deep muscles of the forearm

1. Flexor digitorum Profundus

2. Flexor pollicis longus

3. Pronator quadratus

Flexor digitorum Profundus

Flexor pollicis longus

Pronator quadratus

Lateral radial muscles of the forearm

1. Brachioradialis

2. Extensor carpi radialis longus

3. Extensor carpi radialis brevis

Brachioradialis

Extensor carpi radialis longus

Extensor carpi radialis brevis