Elbow & Forearm Flashcards
Biceps brachii
O:
Long head: Supraglenoid tubercle of the scapula
Short head: Coracoid process (apex)
I: Radial tuberosity, and bicipital aponeurosis
A: Forearm flexion and supination
Shoulder flexion (initial 30°)
Stabilisation of humeral head (during deltoid contraction)
Long head: Shoulder abduction and IR
In: Musculocutaneous n. (C5, C6)
Brachialis
O: Distal half of anterior surface of humerus
I: Ulnar tuberosity, and Coronoid process of the ulna
A: Elbow flexion (most powerful)
In: Musculocutaneous n. (C5, C6), and radial n. (C7)
Triceps brachii
O:
- Long head: infraglenoid tubercle of the scapula
- Medial head: posterior surface of humerus (Distal to radial groove), and medial intermuscular septum
- Lateral head: posterior surface of humerus (proximal to radial groove), lateral intermuscular septum
I: Olecranon of ulna and fascia of forearm
A: Elbow extension
Shoulder extension and adduction (Long head)
In: Radial n. (C6-C8)
Anconeus
O: Lateral epicondyle of the humerus
I: Lateral surface of olecranon
A: Assist Elbow extension
Stabilisation of elbow joint
In: Radial n. (C6-C8)
Pronator teres
O:
Humeral head: Medial epicondyle (common flexor tendon)
Ulnar head: coronoid process of ulna
I: Lateral surface of radius (distal to supinator)
A: Forearm pronation, and elbow flexion (weak)
In: Median n. (C6, C7)
Flexor digitorum superficialis
O:
Humeroulnar head: Medial epicondyle of the humerus (common flexor tendon) and coronoid process of ulna
Radial head: Proximal half of anterior border of radius
I: Middle phalanges II-V
A: MCP and PIP II-V: flexion
Wrist flexion (assist)
In: Median n. (C8, T1)
Flexor digitorum profundus
O: Proximal half of anterior surface of ulna, and interosseous membrane
I: Palmar surface of distal phalanges II-V
A: MCP, PIP, DIP II-V, and wrist flexion
In: Median n. (C8, T1) for II and III, and ulnar n. (C8, T1) for IV and V
Flexor carpi radialis
O: Medial epicondyle of the humerus (common flexor tendon)
I: Base of the metacarpal II (and III)
A: Wrist flexion and abduction
In: Median n. (C6, C7)
Flexor carpi ulnaris
O: Humeral head: Medial epicondyle (common flexor tendon)
Ulnar head: Olecranon
I: Pisiform, Hook of hamate, and base of metacarpal V
A: Wrist flexion and adduction
In: Ulnar n. (C7, T1)
Palmaris longus
O: Medial epicondyle of humerus
I: Palmar aponeurosis, and flexor retinaculum
A: Wrist flexion by tightening the palmar aponeurosis
In: Median n. (C7, C8)
Brachioradialis
O: Lateral surface of the distal humerus, and intermuscular septum
I: (Proximal to) Styloid process of the radius
A: Elbow flexion (with semi pronated)
Forearm semipronation
In: Radial n. (C5, C6)
Extensor carpi radialis longus
O: Lateral supracondylar ridge of distal humerus, and lateral intermuscular septum
I: Dorsal surface of the base of metacarpal II
A: Wrist extension and abduction
(Weak) Elbow flexion
In: Radial n. (C6, C7)
Extensor carpi radialis brevis
O: Lateral epicondyle of the humerus (common extensor tendon)
I: Dorsal surface of the base of metacarpal III
A: Wrist extension and abduction
(Weak) Elbow flexion
In: Radial n. (C7, C8)
Extensor digitorum
O: Lateral epicondyle of humerus (common extensor tendon)
I: Dorsal digital expansion of II-V
A: Wrist extension
MCP, PIP, DIP: extension and abduction
In: Radial n. (C7, C8)
Extensor carpi ulnaris
O: Lateral epicondyle of humerus (Common extensor tendon), and
posterior surface of ulna
I: Base of metacarpal V
A: Wrist extension and adduction
In: Radial n. (C7, C8)
Supinator
O: Lateral epicondyle of humerus, radial collateral ligament, annular ligament, supinator crest of ulna
I: Lateral, posterior, and anterior surfaces of proximal third of radius
A: Forearm supination
In: Radial n. (C6, C7)
(posterior interosseous nerve; C7, C8)
Pronator quadratus
O: Distal anterior surface of ulna
I: Distal anterior surface of radius
A: Forearm pronation
Radioulnar joint stabilisation
In: Median n. (C8, T1)
Common flexor tendon (medial epicondyle of the humerus)
Pronator Teres
Flexor Carpi Radialis
Flexor carpi Ulnaris
Palmaris Longus
Flexor digitorum superficialis
With the exception of Pronator Teres, all are wrist flexors
Common extensor tendon (lateral epicondyle of the humerus)
Extensor Carpi radialis brevis
Extensor Digitorum
Extensor Digiti minimi
Extensor Carpi ulnaris
