Limbs 5 Flashcards
Which nerve roots form the brachial plexus?
C5 to T1
Which anatomical landmark is associated with the brachial plexus?
- subclavian artery
- brachial plexus is lateral to artery
What are some causes of a brachial plexus injury?
- overstretching during collision in contact sports
- to fetus during birth
- trauma during motorvehicle accidents
- tumours
- radiotherapy
What are the signs and symptoms of a brachial plexus injury?
Less severe:
- burning or electric shock sensation down arm
- numbness and weakness of the arm
- short duration of symptoms
More severe:
- weakness or inability to use certain muscles in hand, arm or shoulder
- complete loss of feeling or movement in arm, hand or shoulder
- severe pain
What will injury to the brachial plexus at nerve roots higher on the spinal cord result in?
Injury affects shoulder
What will injuries to the brachial plexus at nerve roots lower on the spinal cord result in?
Affects arm, wrist and hand
Which muscles are affected by a high ulnar nerve injury (at elbow)?
All extrinsic and intrinsic muscles that the ulnar nerve innervates
Which muscles are affected by a low ulnar nerve injury (at wrist)?
Only the intrinsic muscles which the ulnar nerve innervates
Which two digits claw in an ulnar nerve injury?
4 and 5
Why are digits 2 and 3 not clawed during ulnar nerve injury?
They are innervated by the median nerve
Why is clawing more prominent in a low ulnar nerve injury than a high injury?
- high injury = loss of function of flexor digitorum profundus
- low injury = flexor digitorum profundus unaffexted
- so in low injury there is still flexion at the interphalangeal joints, resulting in more prominent clawing
What is the cause of sciatica?
Herniated disc in spine impinging on sciatic nerve
What are the signs and symptoms of sciatica?
- lower back pain which radiates down buttocks and back of one thigh
- pain from buttock to foot
- numbness (severe)
- weakness (severe)
