Elbow myology

Question 1

Triceps

Answer 1

*Origin
- Long Head – Infraglenoid Tubercle
- Lateral Head- Posterior/lateral surface proximal ½ humerus
- Medial Head – Posterior humerus below & medial to lateral head
* Insertion
- Posterior aspect of olecranon
*Action- Elbow extension
Other actions - Long Head – Glenohumeral extension & adduction
* NERVE SUPPLY- Radial nerve (c7,c8)

Question 2

Bicep brachii

Answer 2

*Origin
- Short head: coracoid process
- Long head: supraglenoid tubercle
*Insertion- Radial tuberosity, bicipital aponeurosis
*Action
- Elbow flexion (supination)
- GHJ flexion & abduction
- Supination of forearm
*Nerve- musculocutaneous nerve C5,6

Question 3

Brachioradialis

Answer 3

*ORIGIN- Upper 2/3rds of anterior aspect of lateral supracondylar ridge of humerus
*INSERTION- Lateral surface of radius just above styloid process
*ACTIONS- elbow flexion (mid-position)
OTHER ACTIONS- Returns forearm to mid position from
extremes of pronation & supination
*NERVE SUPPLY- Radial nerve C5,6 & 7

Question 4

Brachialis

Answer 4

*Origin
- distal 2/3rds of anterior surface of humeral shaft
*Insertion
- inferior part of coronoid process
- ulna tuberosity
- elbow joint capsule
*Action- elbow flexion (supination)
-Other actions
- pulls joint capsule away from joint during flexion
*Nerve supply- Musculocutaneus nerve c5,6 & radial nerve c5,

Question 5

Pronator Teres

Answer 5

*Origin
-Humeral Head
> Lower part of medial supracondylar ridge
> Common flexor origin (medial epicondyle)
-Ulnar Head
> coronoid process of the ulna
*INSERTION- Via flat tendon to roughened area on the middle of lateral surface of radius
*Action- Pronation
*NERVE SUPPLY- Median nerve C6, C7

Question 6

Pronator Quadratus

Answer 6

*ORIGIN- Distal ¼ anterior surface of ulna
*INSERTION- Distal ¼ anterior surface of radius
- Triangular area superior to ulna notch of radius
*Actions- pronation
OTHER ACTIONS- Protects the inferior radioulnar joint
*NERVE SUPPLY -Median nerve C8, T1

Question 7

Supinator

Answer 7

*ORIGIN
- Lateral epicondyle
- Radial collateral ligament
- Annular ligament
*INSERTION- Proximal portion of the anterolateral surface of the radius.
*ACTION- supination
*NERVE SUPPLY- Radial nerve C5, C6