MSK - Arm Flashcards
What is the clinical term to describe pins and needs?
Paresthesia
What is olecranon bursitis? And what causes it?
Inflammation and swelling behind the elbow
Trauma, prolonged pressure, infection, medical conditions e.g RA or gout
What muscles are supplied by the musculocutaneous nerve?
All the muscles of the anterior arm
Biceps brachii
Brachialis
Coracobrachialis
Can be recalled as BBC
Where can the scaphoid be palpated?
Anatomical snuff box
What makes up the cubital fossa? (Lateral to medial) (4)
Radial Nerve
Biceps Tendon
Brachial Artery
Median Nerve
‘Really Need Beer To Be At My Nicest’
What are the key structures for concern for a surgical neck fracture of the humerus?
Axillary artery and posterior circumflex artery
What is the effect of damage to the Axillary nerve?
Paralysis to the deltoid and teres minor muscles. The patient will not be able to abduct their arm.
Could have sensory loss of skin over lower deltoid
What two structures does the humerus articulate with posteriorly?
Scapula and clavicle
Name three important anatomical features of the proximal humerus.
Head
Anatomical neck
Surgical neck
Where does the head of the humerus sit?
Glenoid cavity of the scapula
What is the deep groove on the humerus called?
What runs through this groove?
Intertubercular sulcus
The tendon of the long head of the Biceps brachii runs through this groove
In what position is the greater and lesser tubercle situated?
Greater tubercle - located laterally on humerus
Lesser tubercle - located more medially on the bone
What four muscles attach anteriorly to the humerus?
Corocobrachialis
Deltoid
Brachialis
Brachioradialis
What lies in the radial groove on the shaft of the humerus?
Radial nerve
Profunda brachii artery
What type of humerus fracture could easily damage the radial nerve and Profunda brachii artery?
Mid shaft fracture
How would a mid shaft fracture effect wrist extension?
The radial nerve innervates the extensors of the wrist and so when damaged the extensors will be paralysed. This results in unopposed flex ion of the wrist known as wrist drop.
What bones does the distal part of the humerus articulate with?
Radius and ulna at the elbow joint
In what orientation are the epicondyles (projections of bone) on the humerus.
Which is the largest?
Lateral and medial epicondyles
Medial epicondyle is much larger.
Both can be palpated at the elbow
What nerve passes along the posterior side of the medial epicondyle? And where can it be palpated?
Ulnar nerve - can be palpated at medial epicondyle
What are the names of the three depressions on the distal portion of the humerus which accommodate the forearm bones during movement at the elbow?
Coronoid fossa
Radial fossa
Olecrannon fossa
What are the common fractures of falling on a flexed elbow?
What artery may be damaged?
Supracondylar and medial epicondyle
Brachial artery
Medial epicondyle fracture could damage the ulnar nerve - deformity known as ulnar claw.
What does a ‘Popeye sign’ show?
Rupture of the long head of the biceps brachii
The patient would not notice much weakness in the upper limb due to the action of the brachialis and supinator muscles
Where does the coracobrachialis lie in relation to the biceps brachii?
Where does it originate from?
What is its function?
What nerve innervates it?
Deep within the muscle
Coracoid process of scapula
Flexor of the arm at the shoulder
Musculocutaneous nerve C5 C6 C7 (mainly C6)
How many heads does the triceps brachii have?
What is its location?
What are the heads and where do they originate?
What is the role of the tricep?
What nerve innervates it?
What does a tap on the triceps tendon test?
3
Posterior of the arm
Long head - infraglenoid tubercle
Lateral head - humerus, superior to radial groove
Medial head - humerus, inferior to radial groove
Extension at the elbow
Radial nerve
Spinal nerve C7
What are the two heads of the pectoralis major?
What nerve is the pectoralis major innervated by?
What is the function of the pectoralis major?
Clavical are head (attaches to clavicle) and sternocostal head (attaches to sternum) Fibres from both heads attach to edge of inter tubercular groove.
Medial and lateral pectoral nerves dervied from the brachial plexus
Adduct and medially rotate humerus at the shoulder. Clavicular head also performs flexion.
What nerve is the pectoralis minor innervated by?
What effect does contraction of the pectoralis minor have?
Medial pectoral nerve
Depresses the shoulder
What is the function of the Serratus anterior?
What ribs does it originate from?
What nerve is it innervated by?
What is winging of the scapula?
Rotate the scapula - allowing arm to be raised over 90 degrees.
Ribs 2-8
Long thoracic nerve
Damage to long thoracic nerve, Serratus anterior will become paralysed. Pushing against a wall, scapula is no longer held against rib cage and protrudes out.
