Muscles of the Posterior Compartment of the Forearm Flashcards
What is the common origin of posterior compartment of the forearm?
Lateral epicondyle of the humerus.
What is the common action of the posterior compartment of the forearm?
Extension.
What is the common innervation of the posterior compartment of the forearm?
Radial nerve (C7-C8).
What are the 2 muscle groups of the posterior forearm and how many muscles are in each?
Superficial (7)
Deep (5)
What is the origins of brachioradialis?
Lateral supracondylar ridge.
What is the insertion of brachioradialis?
Styloid process of the radius.
What is the action of brachioradialis?
Assists in elbow flexion.
What innervates brachioradialis?
Radial nerve (C6-C7).
What is the origin of extensor carpi radialis longus (ECRL)?
Lateral supracondylar ridge.
What is the insertion of extensor carpi radialis longus?
Base of 2nd metacarpal.
What are the actions of extensor carpi radialis longus?
Wrist extension and radial deviation (abduction).
What innervates extensor carpi radialis longus?
Radial nerve (C6-C7).
What is the origin of extensor carpi radialis brevis (ECPB).
Lateral epicondyle.
What is the insertion of extensor carpi radialis brevis?
Dorsal surface of the base of the 3rd metacarpal.
What are the actions of extensor carpi radialis brevis?
Wrist extension and radial deviation (abduction).
What innervates extensor carpi radialis brevis?
Radial nerve (C6-C7).
What is the origin of extensor digitorum communis (EDC)?
Lateral epicondyle
What is the insertion of extensor digitorum communis (EDC)?
Dorsal digital expansions of digits 2 to 5.
What are the actions of extensor digitorum communis (EDC)?
Wrist and MCP extension.
What innervates extensor digitorum communis (EDC)?
Radial nerve (Posterior interosseous nerve).
What is the origin of extensor digiti minimi (EDM)?
Lateral epicondyle.
What is the insertion of extensor digiti minimi (EDM)?
Dorsal digital expansion of digit 5.
What is the action of extensor digiti minimi (EDM)?
Extension of digit 5.
What innervates extensor digiti minimi (EDM)?
Radial nerve (Posterior interosseous nerve).
What is the origin of extensor carpi ulnaris (ECU)?
Lateral epicondyle.
What is the insertion of extensor carpi ulnaris (ECU)?
Base of 5th metacarpal.
What are the action of extensor carpi ulnaris?
Wrist extension and ulnar deviation (adduction).
What innervates extensor carpi ulnaris?
Radial nerve (Posterior interosseous nerve).
What is the origin of anconeus?
Lateral epicondyle.
What is the insertion of anconeus?
Olecranon process.
What is the action of anconeus?
Elbow extension.
What innervates anconeus?
Radial nerve (C6-C7).
What is the origin of the supinator?
Two heads; Lateral epicondyle and supinator crest of ulna.
What is the insertion of the supinator?
Lateral radius.
What is the action of the supinator?
Supination of forearm.
What innervates the supinator?
Radial nerve.
What are the origins of abductor pollicis longus (APL)?
Ulna, radius and interosseous membrane.
What is the insertion of abductor pollicis longus?
Base of 1st metacarpal.
What is the action of abductor pollicis longus?
Abducts the carpometacarpal joint of digit 1.
What innervates abductor pollicis longus?
Radial nerve.
What are the origin of extensor pollicis longus (EPL)?
Ulna and interosseous membrane.
What is the insertion of extensor pollicis longus?
Distal phalanx of digit 1.
What are the actions of extensor pollicis longus?
Extends all joints associated with digit 1.
What innervates extensor pollicis longus?
Radial nerve.
What are the origins of extensor pollicis brevis (EPB)?
Radius and interosseous membrane.
What is the insertion of extensor pollicis brevis?
Proximal phalanx of digit 1.
What are the actions of extensor pollicis brevis?
Extend carpometacarpal and MCP joints digit 1.
What innervates extensor pollicis brevis?
Radial nerve (Posterior interosseous nerve).
What are the origins of extensor indicis (EI)?
Ulna and interosseous membrane.
What is the insertion of extensor indicis?
Dorsal digital expansion of digit 2.
What are the actions of extensor indicis?
Assists in extending digit 2 independent of other digits.
What innervates extensor indicis?
Radial nerve (Posterior interosseous nerve).
A triangular depression on the posterolateral wrist formed by the abductor pollicis longus, extensor pollicis brevis, and extensor pollicis longus tendons. The scaphoid bone from the floor, the radial artery courses across the scaphoid bone, and the superficial radial nerve and cephalic vein course oner the roof with the hypodermis.
Anatomical snuffbox.
