Lecture 7 - Elbow and Wrist Flashcards
important structures of the radius and ulna
the elbow is comprised of which bones?
- > humerus
- > ulna
- > radius
what are the joints of the elbow
Two primary joints
- > ulnohumeral joint
- > radiohumeral joint
Forearm joint nearby
- > proximal radioulnar joint
list the three ulnohumeral and radiohumeral ligaments/ligament structures and what they do
Articular capsule
- > encloses all three articulations
Medial Collateral ligament
- > provides resistance to valgus (pigeon toe) forces
Lateral collateral ligament
- > provides resistance to varus forces
what is the ligament of the proximal radioulnar joint and what does it do
Annular ligament
- > holds the radial head against the ulna
interosseous membrane
thick structure that keeps the radius and ulna together
movements of the elbow joint
- > flexion and extension
flexor muscles of the elbow
- > biceps brachii *
- > brachialis
- > brachioradialis
O/I/A/I of biceps brachii
Origin
- > (LH) supraglenoid tubercle of the scapula
- > (SH) tip of coracoid process
Insertion
- > radial tuberosity and fascia of forearm
Action
- > supinates forearm and flexes elbow
- > SH resists dislocation of shoulder
Innervation
- > musculocutaneous nerve
important structures of the distal humerus
O/I/A/I of brachialis
Origin
- > distal ½ of the ant. surface of the humerus
Insertion
- > coronoid process and ulna tuberosity
Action
- > flexes the elbow in all positions
Innervation
- > musculocutaneuous nerve, small branch from radial nerve
O/I/A/I of brachioradialis
Origin
- > prox. ⅔ of lateral supracondylar ridge of humerus
Insertion
- > lateral surface of distal end of the radius
Action
- > flexes elbow joint, esp. in semi-pronated position
Innervation
- > radial nerve
Extensor muscles of the elbow
- > triceps brachii
- > anconeus
O/I/A/I of triceps brachii
Origin
Long head: infraglenoid tubercle of the scapula
Lateral head: Post surface of the humerus (sup to the radial groove)
Medial head: Post surface of the humerus (inferior to the radial groove)
Insertion
- > proximal end of the olecranon of the ulna and fascia of the forearm
Action
- > primary extensor of elbow joint, long head resists shoulder dislocation
Innervation
- > radial nerve
O/I/A/I of anconeus
Origin
- > lateral epicondyle of humerus
insertion
- > lateral surface of the olecranon and sup part of the post surface of the ulna
Action
- > assists triceps in extending the elbow and stabilizes the elbow joint, may abduct the ulna during pronation
Innervation
- > radial nerve
O/I/A/I of the supinators
Origin
- > lateral epicondyle of humerus, radial collateral and annular ligaments, supinator fossa, and crest of ulna
Insertion
- > lateral, post, and ant surfaces of proximal ⅓ of radius
Action
- > supinates forearm (rotates radius)
Innervation
- > deep branch of radial nerve
O/I/A/I of pronator quadratus
Origin
- > distal ¼ of ant surface of the ulna
Insertion
- > distal ¼ of anterior surface of radius
Action
- > pronates forearm, binds radius and ulna together
Innervation
- > ant interosseous nerve from median nerve
O/I/A/I of pronator teres
Origin
Humeral head: medial epicondyle of the humerus
Ulnar head: coronoid process of the ulna
Insertion
- > middle convexity of the lateral surface of the radius
Action
- > pronates the forearm and flexes the elbow
Innervation
- > median nerve
name all 8 carpals
*Some Lovers Try Position That They Can’t Handle*
- > scaphoid
- > lunate
- > triquetrum
- > pisiform
- > trapezium
- > trapezoid
- > capitate
- > hamate
joints that make up the wrist
Wrist is composed of
- > radiocarpal joint
- > midcarpal joints
- > intercarpal joints
Nearby forearm joint
- > distal radioulnar joint
ligaments of the radiocarpal joint and what do they do
Posterior/Dorsal ligament
- > restrains flexion
Anterior/palmar ligament
- > restrains extension
Radial collateral ligament
- > restrains ulnar deviation
Ulnar collateral ligament
- > restrains radial deviation
ligaments of the carpal joints and what they do
Anterior and Posterior interosseus carpal ligaments
- > holds carpal bones together, reinforced by the shape and interlocking structure of the bones
Flexor retinaculum
- > roof of the carpal tunnel, which the medial nerve and flexor tendons pass through
characteristics of the carpal tunnel
- > created by the flexor retinaculum
- > contains 9 tendons and 1 nerve
- > flexion will decrease the size of the tunnel, extreme extension will also decrease the size of the tunnel
4 “pillars” of the carpal tunnel
- > hook of the hamate
- > pisiform
- > ridge of the trapezium
- > scaphoid tubercle
wrist movements
flexors of the wrist
- > flexor carpi radialis
- > flexor carpi ulnaris
- > palmaris longus
I/O/A/I of flexor carpi radials
Origin
- > medial epicondyle of the humerus
Insertion
- > base of the 2nd metacarpal
Action
- > flexes and radially deviates wrist joint
Innervation
- > median nerve
I/O/A/I of flexor carpi ulnaris
Origin
Humeral head: medial epicondyle of the humerus
Ulnar head: olecranon and posterior border of the ulna
Insertion
- > pisiform, hook of hamate, and 5th metacarpal bone
Action
- > flexes and ulnarly deviates wrist joint
Innervation
- > ulnar nerve
I/O/A/I of palmaris longus
Origin
- > medial epicondyle of the humerus
Insertion
- > distal half of the flexor retinaculum and palmar aponeurosis
Action
- > flexes the wrist and tightens the palmar aponeurosis
Innervation
- > median nerve
extensors of the wrist
- > extensor carpi radialis longus
- > extensor carpi radialis brevis
- > extensor carpi ulnaris
O/I/A/I of extensor carpi radialis longus
Origin
- > lateral supracondylar ridge of humerus
Insertion
- > base of 2nd metacarpal
Action
- > extend and radially deviates the wrist joint
Innervation
- > radial nerve
O/I/A/I of extensor carpi radialis brevis
origin
- > lateral epicondyle of humerus
Insertion
- > base of 3rd metacarpal
Action
- > extend and radially deviates the wrist joint
Innervation
- > deep branch of radial nerve
O/I/A/I of extensor carpi ulnaris
origin
- > lateral epicondyle of humerus and posterior border of the ulna
Insertion
- > base of the 5th metacarpal
Action
- > extends and ulnarlly deviates wrist join
Innervation
- > deep brand of radial nerve
ulnar deviators of the wrist
- > extensor and flexor carpi ulnaris
radial deviators of the wrist
Extensor carpi radialis longus and flexor carpi radialis
