• Triceps Brachii
• Anconeous

innervation: radial nerve C5-T1

attachments: infraglenoid tubercle of scapula (long head), back of humerus above (lateral head) and below (medial head) radial groove to olecranon process of ulna

actions: extension of forearm at elbow

innervation: radial nerve C5-T1

attachments: lateral epicondyle of humerus to posterolateral surface of olecranon process of ulna

actions: extension of forearm at elbow

innervation: radial nerve C5-T1

attachments: lateral supracondyle ridge of humerus (inferior to brachioradialis) to base of second metacarpal

actions:

• extension of hand at wrist
• ABduction of hand

innervation: radial nerve C5-C7

• Extensor Carpi Radialis Brevis
• Extensor Digitorum
• Extensor Digiti Minimi
• Extensor Carpi Ulnaris
• Extensor Indicis

Thenar Outcrop Muscles

• ABductor Pollicis Longus
• Extensor Pollicis Brevis
• Extensor Pollicis Longus

attachment c.e.t. to base of third metacarpel of hand

actions: extension of hand at wrist, ABduction of hand

attachment: c.e.t. to extensor expansion of digits 2-5

actions: extension of fingers at MCP, PIP, DIP

accessory slip of extensor digitorum

attachment: c.e.t. to extensor expansion of digit 5

actions: extension of little finger at MCP, PIP & DIP joints

attachments: c.e.t. & posterior surface of ulna to base of metacarpel 5

actions:

• extension of hand at wrist
• ADDuction of hand (f.c.u.)

attachments: posterior surface of ulna & interosseous membrance to extensor expansion of digit 2

actions: extension of index finger at MCP, PIP & DIP joints

attachments: lateral olecranon, lateral epicondyle & ligaments of elbow joint to posterior & lateral surface of proximal third of radius

actions: supination

innervations: deep branch of radial nerve C7-C8

• ABductor Pollicis Longus
• Extensor Pollicis Brevis
• Extensor Pollicis Longus

innervation: deep branch of radial nerve C7-C8

These tendons bound to anatomical snuffbox.

Within the snuffbox are the superficial branch of the radial nerve & radial artery, the scaphoid bone forms the floor

attachments: posterior surface of ulna, radius & interosseous membrane to base of first metacarpel

actions: extension & ABduction of thumb

attachments: posterior surface of radius & interosseous membrane to base of proximal phalanx of thumb

actions: extension of carpmetacarpal & MCP joints of thumb

attachments: posterior surface of ulna & interosseous membrance to base distal phalanx of thumb

actions: extension of MCP & IP of thumb

From lateral cord of brachial plexus, pierces coracobrachialis to enter anterior compartment of arm

supplies mm. of flexor compartment

continuing onto forearm as lateral antebrachial cutaneous nerve

From medial cord of brachial plexus

decends medial aspect of arm

becoming superficial as it passes behind medial epicondyle ("funny bone") and enters anterior forearm

supplies flexor carpi ulnaris & one half of flexor digitorum profundus in forearm and has extensive role in hand

damage produces "claw hand"

from medial cord of brachial plexus

supply medial skin of upper limb

from lateral & medial cords of brachial plexus

descends through cubital fossa to extensively supply anterior forearm mm. and also has extensive role in hand

deep branch in anterior forearm is the anterior interosseous nerve

passes through carpal tunnel

from posterior cord of brachial plexus

passes along radial groove (spiral groove) of posterior humerus

supplying mm. of posterior compartment

passes laterally at elbow and splits at the lateral epicondyle into superficial and deep branches of radial nerve at edge of cubital fossa

supplies mm. of posterior forearm

damage produces "wrist drop"