Week 4 - Elbow Joint Flashcards
Define the elbow joint
Hinge joint
Formed by:
- Trochlea + capitulum of humerus
- Trochlear notch of ulna
- Head of radius.
What are the anatomical components of the elbow joint
Articular capsule
Ulnar collateral ligament
Radial collateral ligament
Anular ligament of the radius
What movements occur at the elbow joint
Flexion + extension
Describe the anterior part of the articular capsule of the elbow joint
From radial + coronoid fossae of humerus
To coronoid process of the ulna + the anular ligament of the radius.
Where does the posterior part of the articular capsule of the elbow joint extend from and to?
Extends from:
- Capitulum
- Olecranon fossa
- Lateral epicondyle of humerus
Extends to:
- Anular ligament of radius
- Olecranon of ulna
- Ulna posterior to radial notch.
Describe the look of the ulnar collateral ligament
Thick + triangular ligament
Describe location of the ulnar collateral ligament
Extends from:
- Medial epicondyle of humerus
Extends to:
- Coronoid process
- Olecranon of ulna.
Part of this deepens the socket for the trochlea of the humerus.
Describe the look of the radial collateral ligament
Strong + triangular ligament
Describe location of the radial collateral ligament
Extends from the lateral epicondyle of the humerus to the anular ligament of the radius + radial notch of the ulna.
Anular ligament of the radius
Strong band encircling head of radius holding it in radial notch of the ulna.
What muscles of the arm FLEX the radius + ulna?
Biceps brachii
Brachialis muscles
Brachioradialis muscles
What muscles of the arm EXTEND the radius + ulna?
Triceps brachii
Anconeus
Origin for biceps brachii muscle
LONG HEAD originates from tubercle above glenoid cavity of scapula.
SHORT HEAD originates from coracoid process of scapula.
Insertion point for biceps brachii muscle
Radial tuberosity of radius + bicipital aponeurosis
What actions does the biceps brachii allow?
Flexion of forearm at elbow joint
Supinates forearm at radionulnar joint
Flexion of arm at shoulder joint
Origin for brachialis muscle
Distal, anterior surface of humerus.
Insertion for brachialis muscle
Ulnar tuberosity + coronoid process of ulna.
Action of brachialis muscle
Flexes forearm at elbow joint
Origin for brachioradialis
Lateral border of distal end of humerus
Insertion for brachioradialis
Superior to styloid process of radius
Actions of brachioradialis muscle
Flexion of forearm at elbow joint
Supination + pronation of forearm at radioulnar joints to neutral position.
Origin for triceps brachii
LONG HEAD originates from infraglenoid tubercle (projection inferior to glenoid cavity of scapula).
LATERAL HEAD originates from lateral + posterior surface of humerus.
MEDIAL HEAD originates from entire posterior surface of humerus.
Insertion for triceps brachii
Olecranon of ulna
Action of the triceps brachii
Extension of forearm at elbow joint
Extension of arm at shoulder joint
Origin for anconeus
Lateral epicondyle of humerus.
Insertion for anconeus
Olecranon + superior portion of shaft of ulna.
Action for anconeus muscle
Extension of forearm at elbow joint
Origin for pronator teres
Medial epicondyle of humerus + coronoid process of ulna.
Insertion for pronator teres
Midlateral surface of radius
Action for pronator teres
Pronation of forearm at radioulnar joints
Weakly flexes forearms at elbow joint.
Origin for pronator quadratus
Distal portion of shaft of ulna
Insertion for pronator quadratus
Distal portion of shaft of radius.
Action of pronator quadratus
Pronation of forearm at radioulnar joints.
Origin for supinator muscle
Lateral epicondyle of humerus + supinator crest.
Insertion for supinator muscle
Lateral surface of proximal 1/3rd of radius.
Action of supinator muscle
Supination of forearm at radioulnar joints.
