Upper Limb 2 Flashcards
What are the 3 important muscles of the anterior arm?
What nerve supplies these muscles?
Biceps bracii
Coracobrachialis
Brachialis
Musculocutaneous nerve
What is the origin and insertion of the biceps bracii?
Long head:
- Supraglenoid tubercle of the scapula
- Radial tuberosity
Short head:
- Coracoid process
- Radial tuberosity
What 3 joints does the biceps bracii act on?
Shoulder
Elbow
Radio-ulnar joints
What two muscles arise from the coracoid process?
Short head of the biceps bracii
Coracobrachialis
What groove does the long head of the biceps bracii run in after arising from the supraglenoid tubercle?
Bicipital groove
What is the action of the biceps bracii at each of its joints?
Flexes shoulder and elbow joint
Supination of the radio-ulnar joint
Which segmental fibres mainly innervate biceps bracii?
C5 and C6
From which cord of the brachial plexus is the musculocutaneous nerve a branch of?
Lateral cord
What is the origin and insertion of the coracobrachialis?
Tip of the coracoid process
Medial margin of the humerus about its middle
What is the action of the coracobrachialis on the shoulder joint?
Flexion and adduction
What is the nerve supply of the coracobrachialis?
Musculocutaneous nerve
What is the origin and insertion of the brachialis?
Arises from the front of the distal half of the shaft of the humerus
Inserted into coronoid process of ulna
What is the main action of the brachialis on the elbow joint?
Flexes elbow in all positions
What nerve supplies the brachialis muscle?
Musculocutaneous nerve
What muscle does the musculocutaneous nerve perforate to enter the arm?
Coracobracialis
Between which two muscles does the musculocutaneous nerve descend between?
Biceps bracii
Brachialis
After supplying the muscles of the arm what does the musculocutaneous nerve continue as?
Lateral cutaneous nerve of the forearm
What is the segmental or root value of the musculocutaneous nerve?
C5-C7
Injury to the musculocutaneous nerve from a weapon such as a knife would result in what?
Paralysis of biceps bracii, coracobrachialis and brachialis
Loss of sensation on the lateral aspect of forearm
Where does the brachial artery start and end?
Direct continuation of the axillary artery which begins at the lower border of teres major muscle and ends in the cubital fossa close to the neck of the radius dividing into radial and ulnar arteries