MSK Session 3- The Arm And Cubital Fossa Flashcards
What are the proximal attachments of the heads of the biceps?
- long head- attaches at the supraglenoid tubercle of the scapula.
- short head- attaches to the coracoid process
What are the three anterior arm muscles and what is their primary function?
Biceps brachii, brachialis, coracobrachialis
Flexion
What are the 2 action of the biceps?
- flexion of the forearm at the elbow
- supination of the flexed forearm
What is the innervation of the biceps brachii?
Musculocutaneous nerve (C5,6,7)
What are the proximal and distal attachments of the brachialis?
- proximal- distal half of the humerus
- distal- coronoid process and ulna tuberosity.
What is the action of the brachialis muscle?
Flexion of the forearm at the elbow, at all positions
What is the innervation of the brachialis?
Musculocutaneous nerve (C5,6,7)
What is the proximal and distal attachments of coracobrachialis?
- proximal- coracoid process
- distal- middle third of the medial humerus
What are the two main functions of coracobrachialis?
-flexion and adduction of the arm
What is the innervation of the coracobrachialis?
Musculocutaneous nerve (C5,6,7)
What are the two posterior arm muscles and what is their innervation?
Triceps brachii and anconeus
Radial nerve
What is the action of triceps? (2)
Extension of the forearm at the elbow joint
Steadies the head of the humerus during abduction
What is the action of anconeus? (2)
Aids the triceps during extension
Abducts the ulna during pronation
What is the main artery supplying the arm?
Brachial artery
When does the axillary artery becomes the brachial artery?
Once it has passed the inferior border of teres major.
What are the three branches of the brachial artery and when do they arise?
- radial and ulnar arteries arise in the apex of the cubital fossa
- profunda brachii artery arises at the inferior border of teres major and lies with the radial nerve in the radial groove of the humerus.
List the progression of veins (distal to proximal)
Median antebrachial vein
Median cubital vein
Basilic and cephalic veins
Axillary vein
What are the 5 borders of the cubital fossa?
Superior- imaginary line between the medial and lateral epicondyle
Medial- pronator teres
Lateral- Brachioradialis
Roof- skin, fascia and bicipital aponeurosis
Floor- brachialis and supinator
What are the contents of the cubital fossa from lateral to medial?
Bicipital tendon
Brachial artery
Median nerve
What is strange about Brachioradialis?
It is a flexor of the forearm at the elbow, but is innervated by the radial nerve.