Lecture 8 Flashcards
What is the innervation of all posterior forearm compartment muscles?
Radial nerve
What is the origin and insertion of brachioradialis?
origin: proximal 2/3 of lateral supracondylar ridge of humerus
insertion: lateral surface of distal end of radius proximal to styloid process
Where do majority (not all) posterior forearm compartment muscles originate?
common extensor tendon on lateral epicondyle
What is the action of brachioradialis?
flexion of forearm (mid-pronation)
What is the innervation of brachioradialis ?
radial nerve
What is the origin and insertion of extensor carpi radialis longus?
Ori: Distal 1/3 of lateral supracondylar ridge of humerus
Ins: Base of 2nd metacarpal bone
What is one of the only muscles of the superficial layer of the posterior compartment of the forearm that does not go to the common extensor tendon?
extensor carpi radialis longus
What is the function of extensor carpi radialis longus?
Extension of hand at wrist
Radial deviation (abduction) of wrist
Extension of elbow (weak)
What is the innervation of extensor carpi radialis longus?
radial nerve
What is the origin and insertion of extensor carpi radialis brevis?
Ori: Lateral epicondyle of humerus (via common extensor tendon)
Ins: Base of 3rd metacarpal bone
What is the function of extensor carpi radialis brevis?
Extension of hand at wrist
Radial deviation (abduction) of wrist
What is the innervation of extensor carpi radialis brevis?
radial nerve
Who composes the Mobile Was of 3?
brachioradialis, extensor carpi radialis longus and brevis
What is the origin and insertion of extensor digitorum?
Ori: Lateral epicondyle of humerus (via common extensor tendon)
Ins: Distal and middle phalanges of fingers #2 – 5
(via its dorsal digital expansion)
What is the function of extensor digitorum?
Extension of fingers 2-5 at MCP, PIP, DIP joints
Extension of hand at wrist
Extension of elbow (weak)
What is the innervation of extensor digitorum?
radial nerve
What is the origin and insertion of extensor digiti minimi?
Ori: Lateral epicondyle of humerus (via common extensor tendon)
Ins: Middle and distal phalanges of little finger (via its dorsal digital expansion)
what is the function of extensor digiti minimi?
extension of finger 5 at MCP, PIP, DIP joints
Extension of hand at wrist
Extension of elbow (weak)
What is the innervation of extensor digiti minimi?
radial nerve
What is the origin and insertion of extensor carpi ulnaris?
Ori:
- Lateral epicondyle of humerus (via common extensor tendon)
- Posterior border of ulna
Ins: Base of 5th metacarpal bone.
What is the function of extensor carpi ulnaris?
Extension of hand at wrist
Ulnar deviation (adduction) of wrist
Extension of elbow (weak)
What is the innervation of extensor carpi ulnaris?
radial nerve
What is the origin and insertion of aconeus?
Ori: Lateral epicondyle of humerus
Ins:
- Olecranon process of ulna
- Proximal of posterior surface of ulna
What is the action of aconeus?
extension of forearm at elbow (weak)