Upper Limb 2 Flashcards
What is the most anterior muscle of the anterior arm?
Biceps brachii
What is the origin of biceps brachii?
Short head: coracoid process
Long head: supraglenoid tubercle
Where does the biceps tendon insert?
Tuberosity of radius
What is the action of the biceps brachii?
Shoulder and elbow flexion, supination at RU joint
What is the nerve supplying the anterior compartment of the arm?
Musculocutaneous
What is the nerve roots of the musculocutaneous nerve?
C5-7
Which two muscles have their origins at the coracoid process?
Coracobrachialis and biceps brachii
Where does the coracobrachialis insert?
Medial margin of humerus
What is the action of the corachobrachialis?
Flexion and abduction at shoulder
Where is the origin of the brachialis?
Humeral shaft
Where does brachialis insert?
Coronoid process of ulnar
What is the action of brachialis?
Flexion of elbow
From which cord of the brachial plexus does the musculocutaneous nerve arise?
Lateral
What muscle does the musculocutaneous nerve pierce?
Coracobrachialis
After supplying the muscles of the arm, what does the musculocutaneous nerve become?
Lateral cutaneous nerve of the forearm
What does the lateral cutaneous nerve of the forearm supply?
Sensation to the lateral aspects of the forearm
What kinds of injuries may damage the musculocutaneous nerve and what would result from damage to the musculocutaneous nerve?
Penetrating injury to axilla
Would result in paralysis of corachobrachialis, biceps brachii, brachialis and loss of sensation to lateral forearm
What is the brachial artery a continuation of?
Axillary artery
When does the axillary artery become the brachial artery?
Lateral border of teres major
Where does the brachial artery end and what does it become?
In cubital fossa as it splits into radial and ulnar arteries
What important branch does the brachial artery give off in the arm?
Profunda brachii
From which cords of the brachial plexus does the median nerve arise?
Lateral and medial cords
How can you identify the median nerve on a cadaver?
Enters cubital fossa and doesn’t give any branches in arm
What does the median nerve supply?
All muscles of anterior forearm apart from flexor carpi ulnaris and ulnar half of flexor digitorum profundus
From which cord on the brachial plexus does the ulnar nerve arise?
Medial
How can you identify the ulnar nerve on a cadaver?
Goes round medial epicondyle and runs along medial head of triceps
What does the ulnar nerve supply?
FCU and ulnar 1/2 of FDP
Where is the radial nerve vulnerable to damage?
Fracture of radial groove
Where is the ulnar nerve vulnerable to damage?
Fracture at medial epicondyle
Where is the axillary nerve vulnerable to damage?
Fracture at surgical neck
What makes up the borders of the cubital fossa?
Line between epicondyles
Medial border: pronator teres
Lateral border: brachioradialis
What are the contents of the cubital fossa?
Brachial artery (or radial/ulnar artery)
Accompanying veins
Biceps tendon
Median and radial nerves
Where is the origin of the triceps brachii?
Long head - infraglenoid tubercle
2 shorter heads - humerus
Where does the triceps tendon insert?
Olecranon of ulnar
What is the function of the triceps?
Extension of elbow
What nerve supplies the whole posterior compartment of the arm and forearm?
Radial nerve
What is the action of the aconeus?
Assists triceps in extending elbow and stabilises elbow joint
From which branch in the brachial plexus does the radial nerve arise?
Posterior cord
Next to which artery does the radial nerve run in the arm?
Profunda brachii artery
What is the root value of the radial nerve?
C5-T1
What occurs in radial nerve injury?
Wrist drop
What kind of joint is the elbow?
Synovial hinge
What actions occur at the elbow joint?
Flexion and extension
What are the extensors of the elbow?
Triceps brachii and aconeus
What are the flexors of the elbow?
Biceps brachii, brachialis, bracoradialis
What are the ligaments of the elbow?
Lateral/radial collateral, medial/ulnar collateral and annular ligament of radius
What does the annular ligament of the radius do?
Holds the head of the radius
What is student’s elbow?
Olecranon bursa becomes inflamed due to injury/infection/repeated friction e.g. leaning on elbow
What kinds of joints are the proximal and distal radioulnar joints?
Synovial pivot
What movements occur at the radioulnar joints?
Supination and pronation
What are the supinators of the forearm?
Mostly biceps brachii
Others: supinator muscle of forearm, extensor pollicis longus, extensor carpi radialis longus
What are the pronators of the forearm?
Mostly pronator quadratus
Others: pronator teres, flexor carpi radialis, palmaris longus, brachioradialis
What is the name of the condition where the radial head falls out of the annular ligament?
Elbow subluxation
