2. Arm & Shoulder Flashcards
What is the origin of the coracobrachialis muscle?
Tip of coracoid process of scapula
What is the insertion of the coracobrachialis muscle?
Middle third of medial surface of humerus
What nerve innervates the coracobrachialis?
Musculocutaneous
What 2 muscle attach proximally to the coracoid process?
Short head of biceps brachii and coracobrachialis
What is the main action of the coracobrachialis muscle?
Flexion and adduction of shoulder joint
What is the origin of each head of the biceps brachii?
Short head - tip of coracoid process of scapula
Long head - supraglenoid tubercle of scapula
What is the distal attachment of the biceps brachii muscle?
Tuberosity of radius and fascia of forearm via bicipital apaneurosis
What nerve innervates the biceps brachii muscle?
Musculocutaneous
Which 3 muscles in the arm are innervated by the musculocutaneous nerve?
Biceps brachii
Brachialis
Coracobrachialis
“BBC”
What is the main action of the biceps brachii?
Flexes arm at elbow joint
Flexes arm at shoulder joint
Supinates forearm
Short head resists dislocation of shoulder
What is the origin of the brachialis muscle?
Distal half of anterior surface of humerus
What is the insertion of the brachialis muscle?
Coranoid process and tuberosity of ulna
What is the main action of brachialis muscle?
Flexes elbow joint in all positions
What is the origin of pronator teres?
Ulnar head: coronoid process of ulna
Humoral head: medial epicondyle of humerus
What is the distal attachment of the pronator teres muscle?
Lateral aspect of mid shaft of the radius
What is the main action of the pronator teres muscle?
Pronates and flexes forearm
What is a major branch of the brachial artery in the arm?
Profunda brachii (deep brachial)
What is the superior boundary of the cubital fossa?
Imaginary line connecting the medial and lateral epicondyles
What is the medial border of the cubital fossa?
Pronator teres
What is the lateral border of the cubital fossa?
Brachioradialis
What are the contents of the cubical fossa?
- brachial artery branches into radial and ulna arteries.
- biceps brachii tendon
- median nerve
- radial nerve, dividing into deep and superficial branches
- median cubital vein
Which muscles are termed the ‘rotator cuff’ muscles?
Subscapularis Infraspinatus Teres minor Supraspinatus (SITS)
Which nerve supplies the trapezius?
Accessory nerve
Which muscles in the arm are innervated by the radial nerve?
Triceps brachii
Which blood vessel branches of the brachial artery accompany the axillary nerve ?
Posterior circumflex humoral vessels.
What is the relationship of structures in the cubital fossa, lateral to medial?
“TAN”
Tendon of biceps brachii
Artery (brachial)
Nerve (medial)
What bones is the shoulder girdle made up of?
Clavicle and scapula
What is the function of the shoulder girdle?
Connect the arm to the axial skeleton
What type of joint is the glenohumeral joint?
Ball and socket
What is the function of the glenoid labrum?
Fibrocartilaginous rim attached to the glenoid cavity to deepen the cavity.
What are the 3 extra-capsular ligaments which attach to the coracoid process?
- Coracohumeral ligament
- Coracoacromial ligament
- Coracoclavicular ligament
Which rotator cuff muscles attach at the greater tuberosity of the humerus?
Supraspinatus
Infraspinatus
Teres minor
Which rotator cuff muscle attaches to the lesser tuberosity of the humerus?
Subscapularis
Which muscles does the suprascapular nerve innervate?
Supraspinatus
Infraspinatus
What nerve supplies the teres minor?
Axillary nerve
Which nerve innervates the subscapularis ?
Upper and lower subscapular nerves.
What is the function of the rotator cuff muscles?
Stabilise the shoulder joint
Which rotator cuff muscles initiates ABduction of the shoulder joint?
Supraspinatus
Which rotator cuff muscles externally rotate the shoulder joint?
Infraspinatus
Teres minor
What rotator cuff muscles internally rotate the shoulder joint?
Subscapularis
Which joint is responsible for the first 90 degrees of shoulder abduction?
Glenohumeral joint
0-15 degrees = supraspinatus
15-90 degrees = deltoid
Which joint is responsible for abduction of the shoulder joint over 90 degrees, how does it achieve this and what muscles are involved?
Scapulo-thoracic joint through scapula rotation.
Upper trapezius and serratus anterior muscles.
What muscles are responsible for adduction of the shoulder joint ?
Pectoralis major
Latissimus dorsi
Teres major
Which nerve innervates the latissimus dorsi and teres major muscles?
Thoracodorsal n.
Which muscles are involved in flexion of the shoulder joint?
Anterior deltoid
Pectoralis major
Coracobrachialis
Biceps brachii
Which muscles are responsible for extending the shoulder joint?
Posterior deltoid
Latissimus dorsi
Teres major
Which muscles cause internal rotation of the shoulder joint?
Subscapularis
Teres major
Pectoralis major
Latissimus dorsi
Which muscles initiate external rotation of the shoulder joint?
Infraspinatus
Teres minor
Which branches of the axillary artery wrap around the proximal head of the humerus ?
Anterior and posterior circumflex arteries
