Dissection: Upper Limb Flashcards
Which muscle retracts the scapula?
Rhomboids
Which muscle protracts the scapula?
Serratus anterior
Which muscles elevate the scapula?
Levator scapulae and upper trapezius
Which muscles depress the scapula?
Latissimus dorsi and lower trapezius
What is the nerve supply to the trapezius?
CN XI (spinal accessory nerve)
What is the nerve supply to the levator scapulae and rhomboids?
Dorsal scapulae nerve (C3,C4,C5)
What is the nerve supply to serratus anterior?
Long thoracic nerve
What is the nerve supply to teres major?
Subscapular nerve
What is the nerve supply to teres minor?
Axillary nerve
What is the nerve supply to subscapularis?
Subscapular nerve
What is the nerve supply to supraspinatus and infraspinatus?
Suprascapular nerve
What are the boundaries of the axilla?
Anterior = pectoralis minor and major Posterior = Subscapularis, latissimus dorsi and teres major Medial = serratus anterior and rib cage Lateral = bicipital groove of humerus
Name the 5 terminal branches of the brachial plexus
Axillary, radial, musculocutaneous, median, ulnar
Name the three cords of the brachial plexus
Posterior, lateral and medial
Which nerves stem from the posterior cord of the brachial plexus?
Axillary and radial
Which nerves stem from the lateral cord of the brachial plexus?
Musculocutaneous (and gives rise to median)
Which nerves stem from the medial cord of the brachial plexus?
Median nerve (with branches from lateral cord also) and ulnar nerve
Which nerve roots supply the musculocutaneous nerve?
C5,6,7
What does the musculocutaneous nerve innervate?
Motor = brachialis, biceps brachialis and coracobrachialis (BBC - flexors)
Sensory: lateral forearm
How is the musculocutaneous nerve damaged, and what are the symptoms?
How? Deep laceration (rare)
Signs = paralysis of arm flexors
Which nerve roots supply the median nerve?
C5-T1
What does the median nerve innervate?
Motor: Flexors of forearm (except for flexor carpi ulnaris and the ulnar 1/2 of flexor digitorum profundus), lateral (radial) 2 lumbricals and thenar (thumb) muscles
Sensory: First radial 3 1/2 digits on palm of hand and tips of first radial 3 1/2 digits on dorsal surface
How may the median nerve be damaged?
Supracondylar fracture OR carpal tunnel compression
What are the symptoms of median nerve damage?
Hand of benediction whereby, when asked to make a fist, the individual can only flex the first 1 1/2 ulnar digits (involves flexion of DIP and PIP by the lumbricals which has lost medial innervation)
Which nerve roots supply the ulnar nerve?
C8-T1
What does the ulnar nerve innervate?
Motor: FCU, FDP (ulnar half) and all hand muscles except thenar and 2 lateral lumbricals
Sensory: to dorsal and palmar sides of first 1/2 ulnar digits and associated palm
How may the ulnar nerve be damaged?
Medial epicondyle fracture OR deep wrist laceration
What are the symptoms of ulnar nerve damage?
Develop ulnar claw whereby the first 2 ulnar digits extend at the MCP and flex at the DIP and PIP
Which nerve roots supply the axillary nerve?
C5,C6
What does the axillary nerve innervate?
Motor: deltoid and teres minor
Sensory: regimental patch on shoulder
How may the axillary nerve be damaged?
Dislocated shoulder or fracture of humeral neck
What are the symptoms of axillary nerve damage?
Inability to abduct shoulder (greater than 10 degrees - done by supraspinatus) due to paralysis of deltoid
Which nerve roots supply the radial nerve?
C5-T1
What does the radial nerve innervate?
Motor: all extensor muscles of arm and forearm (posterior compartment)
Sensory: Posterior aspect of arm and forearm and the 1st dorsal interosseous web
How may the radial nerve be damaged?
Midshaft fracture to the humerus (travels in spiral groove)
What are the symptoms of radial nerve damage?
Wrist drop - due to loss of innervation to extensors of the forearm
What are the boundaries of the deltopectoral triangle?
lateral border of pectoralis major (clavicular head), the clavicle and the anterior deltoid muscle
What are the contents of the deltopectoral triangle?
Cephalic vein, subclavian artery, subclavian vein
What are the boundaries of the quadrangular space?
Superior = teres minor Inferior = teres major Lateral = humerus Medial = long head of triceps
What are the contents of the quadrangular space?
Axillary nerve and posterior circumflex (humerus) artery and vein
What are the boundaries of the triangular interval?
Superior = teres major Medial = long head of triceps Lateral = humerus
What are the contents of the triangular interval?
Radial nerve and profunda brachii artery
What are the boundaries of the cubital fossa?
Lateral = brachioradialis Medial = pronator teres Superior = imaginary line between 2 epicondyles Roof = antebrachial fascia and bicipital aponeurosis Floor = brachialis and supinator
What are the contents of the cubital fossa?
Radial nerve, medial nerve, biceps tendon, brachial artery
