Brachial Plexus Injuries Flashcards
How do injuries to the upper brachial plexus typically arise?
An excessive increase in the angle between neck and shoulder.
1) trauma
2) childbirth- excessive traction applied to the babies neck if the shoulders become stuck on the pelvis (shoulder dystocia)
Which nerve roots are affected in upper brachial plexus injuries?
C5 and C6
What is the effect of injuries to the upper brachial plexus?
Sensory alteration to dermatomes and paralysis of muscles supplied by nerve roots:
C5: shoulder abduction and external rotation
C6: elbow flexion, wrist extension and supination
Which muscles are likely to be paralysed by upper brachial plexus injury?
- Deltoid (axillary nerve C5-C6)
- teres minor (axillary nerve C5-C6)
- biceps brachii (musculocutaneous nerve C5,C6,C7)
- brachioradialis (radial nerve C5, C6, C7, C8, T1)
- brachialis (musculocutaneous nerve C5,C6,C7)
- coracobrachialis (musculocutaneous nerve C5,C6,C7)
What is the name given to the injury caused by upper brachial plexus injury? Describe the appearance.
Erb’s Palsy
Arm hags medially rotated with an adducted arm and extended elbow
How are injuries to the lower brachial plexus usually caused?
Due to forced hyper extension/ hyperabduction
1) falling from height grabbing tree branch
2) baby’s arm delivered first in childbirth
Which nerve roots are affected in injury to the lower brachial plexus?
C8 and T1
What is injury to the lower roots of the brachial plexus otherwise known as?
Klumpke’s Palsy
With injury to the the lower brachial plexus, which motions will be affected?
C8: finger flexion and extension
T1: finger abduction and adduction
What pattern of deformity in the hand will you see in Klumpke’s palsy?
Claw hand with hyperextension ALL the MCPJ and flexion of the interphalangeal joints. The thumb is abducted
