Nerve Palsies of the Limbs Flashcards
What are more common: upper limb palsies or lower limb palsies?
Upper limb palsies
What are the common sites of nerve entrapment?
Nerve roots Peripheral nerves Brachial plexus Sacral plexus Lumbar plexus
What is Hilton’s law?
Hilton’s law states that a sensory nerve supplying a joint also supplies the muscles moving the joint and the skin overlying the joint
What are the different types of brachial plexus palsies?
Upper brachial plexus palsies affecting C5 and C6 known as Erb’s palsy
Lower brachial plexus palsies affecting C8 and T1 known as Klumpke’s palsy
Total brachial plexus palsies that affect all of C5-T1
What are the characteristics of Erb’s palsy?
More commonly affects neonates and is rarer in adults
When it does occur in adults it is usually due to high energy injuries
Erb’s results in a waiter’s tip position, with the shoulder adducted, elbow extended and pronated and the wrist is flexed
How does Klumpke’s palsy present?
Affects small muscles in hand and results in a claw hand
What is the cause of radial nerve palsy?
Pressure on radial nerve due to lying on the nerve during sleeping
What are the symptoms of radial nerve palsy?
Vary depending on site of entrapment as follows:
• In axilla- loss of elbow extension, wrist extension and sensory changes in the wrist and forearm
• In arm- loss of wrist extension and sensory loss
• In forearm- loss of finger extension
• At wrist- loss of sensation (eg handcuffs)
What are the causes of carpal tunnel syndrome?
Trauma
Swellings
Inflammatory disease
Metabolic disease
How doe carpal tunnel syndrome present?
Nocturnal pain and paraesthesia in part or all of the median nerve distribution
Wasting of the thenar muscles can also occur but this is a very late sign
How is carpal tunnel syndrome examined clinically?
Check for thenar muscle wasting, previous scars and deformity
Feeling to test sensation
Movements to test APB power
Specific tests are Tinnels and Phalens
How is carpal tunnel syndrome treated?
Surgically with carpal tunnel release
What are the symptoms of cubital tunnel syndrome?
Numbness on ulnar side of hand
Difficulty with fine tasks
Muscle wasting of first webspace causing guttering and hypothenar wasting
Ulnar claw hand can also present, with a distal lesion causing more severe symptoms than proximal lesions
How is cubital tunnel syndrome assessed clinically?
Froment’s test (is ulnar nerve is palsied then patient will have to use FPL to grip newspaper rather than adductor pollicis)
What are the characteristics of meralgia paraesthesia?
Altered sensation and pain in lateral thigh
Caused by compression of the lateral femoral cutaneous nerve of thigh as it passes under the lateral border of the inguinal ligament
