Brachial plexus lesions

Question 1

Superior part of the plexus (C5, C6) lesion

Answer 1

Injuries can result when an adult has been thrown off a motorbike or horse, or when they fall and their shoulder is the first thing to hit the ground

May also occur if during childbirth there has been excessive stretching of the neck (results in stretching or tearing of superior part of plexus)

– Erb’s palsy:
—- may result in paralysis of deltoid, biceps, brachial and brachioradialis
—- presentation:
—— pt shoulder medially rotated and elbow extended
—— there may be loss of sensation over the upper lateral arm (‘Waiter’s tip’ deformity)

– Backpacker’s palsy:
—- repetitive micro trauma from carrying a heavy backpack (can result in superior brachial plexus injury)

Question 2

Compression of the cords (lateral, medial and posterior)

Answer 2

Can result from:
– prolonged hyperabduction of the shoulder during overhead activities (painting)
– the cords are compressed between the coracoid process of the scapula and pectorals minor (space occupying lesions (cancer) may also compress cords)

Question 3

Inferior part of the plexus (C8, T1) usually

Answer 3

Typically occurs when the upper limb is suddenly pulled superiorly

Kulpke’s palsy:
– can be caused by:
—- difficult breech delivery
—- cervical rib
—- abnormal insertion or spasm of the anterior and middle scalene muscles occurring at child birth

Symptoms:
– paralysis of intrinsic hand muscles (claw hand)
– ulnar nerve distribution numbness