Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
|
role of elbow joint
|
-application of force
-controlling the placement of the hand in space -help us perform many activities of daily living |
|
|
3 joints at the elbow
|
humeroulnar joint
humeroradial joint proximal radioulnar joint |
|
|
elbow ligaments
|
radial collateral
-connects radius to humerus ulnar collateral -connects ulna to humerus annular -keeps radial head in radial notch of ulna |
|
|
humeroulnar joint
|
hinge joint
1 DF very stable -depth of trochlear notch -snug fit of trochlear notch over trochlear condyle -surrounding articular cartilage coronoid process limits flexion ROM olecranon process limits extension ROM |
|
|
humeroradial joint
|
Gliding joint
-flexion/extension -pronation/supination no contact between humeral capitulum and radial head when extended anterior radial head slides into radial notch in flexion |
|
|
radioulnar joint
|
promimal and distal joints
-proximal --reinforced by annular ligament --pronation/supination |
|
|
motions at humeroulnar joint
|
Flexion
Extension |
|
|
Muscles that produce flexion
|
Brachialis
Biceps Brachii Brachioradialis Pronator teres |
|
|
Brachialis facts
|
-max force at 120 degrees flexion
-inserts on the ulna -provides flexion in all radioulnar positions -musculocutaneous n. |
|
|
Biceps brachii facts
|
-greatest flexion force between 30-120 degrees
-greatest in neutral or supinated wrist -inserts on the radius -force improves with shoulder hyperextension -musculocutaneous n. |
|
|
reasons why biceps brachii is weak in pronation
|
-radial rotation during pronation twists biceps insertion under the radius
-interfers with flexion -only active against resistance |
|
|
brachiradialis facts
|
-strongest in neutral
-max force at 120 degrees -can act as a supinator or pronator -radial n. |
|
|
pronator teres facts
|
-provides additional force to over come high resistance
-median n. |
|
|
muscles of elbow extension
|
triceps brachii
anconeus |
|
|
triceps brachii facts
|
-three heads
--medial head- workhorse extensor --long head- least active --lateral head--strongest -inactive unless against resistance --law of parsimony ---As force increases, small one-joint muscles are recruited first, then larger two-joint muscles are recruited second to only use as much force as needed -radial n. |
|
|
anconeus facts
|
-STABILIZES ELBOW JOINT
-works with tricpes to extend elbow -abducts ulna during forearm pronation -radial n. |
|
|
motions occuring at the radioulnar joint
|
pronation
supination |
|
|
muscles of pronation
|
pronator teres
pronator quadratus |
|
|
pronator teres facts
|
-most active at 60 degrees elbow flexion
-median n. |
|
|
pronator quadratus facts
|
-greater activity that pronator teres
-median n. |
|
|
muscles of supination
|
biceps brachii
supinator |
|
|
biceps brachii facts
|
AS A SUPINATOR
-provides motion around the proximal radioulnar joint -max force at 90 flexion -unwanted flexion is neutralized by tricpes activation |
|
|
supinator facts
|
-provides supination at all elbow flexion angles
-radial n. |
|
|
muscles innervated by the musculocutaneous n.
|
brachialis
bicpes brachii |
|
|
muscles innervated by the radial n.
|
brachioradialis
triceps brachii anconeus supinator |
|
|
muscles innervated by the median n.
|
pronator teres
pronator quadratus |
