Name fourtypes of humeral fracture
Surgical, Midshaft, Supracondylar, Medial Epicondylar
What is damaged in a surgical fracture of the humerus?
Posterior circumflex artery and axillary artery
Axillary nerve
What does damage to the axillary nerve cause in a surgical fracture?
Loss of motor function of teres minor and deltoids
Loss of sensation to regimental badge area
What does a midshaft fracture cause damage?
Radial nerve damage, causing wrist drop due to extensor paralysis and unopposed flexion
What type of fracture is a midshaft fracture of the humerus?
Spiral
What damage does a supracondylar fracture do?
Damages brachial artery, leading to loss of blood supply to flexors resulting in volkmans ischaemic contractures. Flexors shortan and cause uncontrolled flexion.
What does a medial epicondylar fracture of the humerus cause?
Damages ulnar nerve and ulnar claw becomes apparent
What are the four rotator cuff muscles?
SITS Supraspinatus Infraspinatus Teres Minor Subscapularis
Action and innvervation of supraspinatus
Suprascapular nerve
Abduction up to 15*
Action and innervation of infraspinatus
Supracscapular nerve
Lateral rotation of the arm
Action and innervation of subscpularis
Upper and lower subscapular nerve
Prevents displacement of the head of the humerus
What is the action of the rotator cuff mmuscles together?
Stabilisation of the glenohumeral joint
What is painful arc syndrome?
Normally: Supraspinatus rubs against the coraco-acromial arch, friction of which is usually reduced by subacromial bursa.
HOWEVER
Pain in the middle of abduction when the supraspinatus tendon comes into contact with the acromion due to degenerative changes in both the supraspinatus tendin and the subacromial bursa
What are the three muscles of the arm?
BBC
Biceps
Brachialis
Coracobrachialis
What is the attachment of the bicep?
Long head at the supraglenid tubercle, short head at the coracoid process
Attaches distally to the radial tuberosity
What is the aciton of the bicep?
Responsible for supination of forearm and flexion at the elbow and shoulders
What is popeye sign?
Bulging bicep after rupture of the long tendon of the biceps. Very littleweakness on flexion due to actions of the supinator and brachialis.
What is the origin of the corachobrachialis?
Coracoidprocess of scapula
What is actions of the corachobrachialis?
Flexion at shoulder
What is the innervation of the three arm muscles?
Musculocutaneous nerve
What is the action of the brachialis?
The brachialis muscle is the main flexor at the elbow
What is the attachment of the brachalis?
It originates from the medial and lateral surfaces of the humeral shaft, and inserts into the tuberosity of ulna just distal to the elbow joint.
