Nerve palsies in the limbs Flashcards
Where can nerve palsies originate in the limbs?
Nerve roots
Brachial plexus
Peripheral nerves
What plexus supplies the upper limbs?
Brachial plexus
What plexus supplies the lower limbs?
Sacral and lumbar plexus
What are the peripheral nerves of the upper limbs?
Axillary nerve Radial nerve Musculocutaneous nerve Ulnar nerve Median nerve
What are the peripheral nerves of the lower limb?
Sciatic nerve
Femoral nerve
Common peroneal nerve
Lateral femoral cutaneous nerve
What is a dermatome?
The area of skin supplied by a spinal root
What dermatomes cover the upper limb?
C4-T2
What dermatomes cover the lower limb?
L1-S2
What is the myotome of the elbow flexors?
C5
What is the myotome for the wrist extensors?
C6
What is the myotome for the elbow extensors?
C7
What is the myotome for the finger Flexors?
C8
What is the myotome for the intrinsic hand muscles?
T1
What is the myotome for the hip flexors?
L2
What is the myotome for the knee extensors?
L3
What is the myotome for the ankle dorsiflexors?
L4
What is the myotome for the long toe extensors?
L5
What is the myotome for the ankle plantar flexors?
S1
What are palsies of the brachial plexus?
Erb’s palsy - C5-C6
Klumpke’s palsy - C8-T1
Total brachial plexus
What are palsies for the upper limb peripheral nerves?
Axillary nerve palsy -secondary to trauma
Radial nerve palsy - secondary to compression or entrapment
Median nerve - carpal tunnel syndrome
Ulnar nerve - Cubital tunnel syndrome
What causes Erb’s palsy?
Stretch of the brachial plexus during birth
What is the waiter’s tip position a sign of?
Erb’s palsy
What is waiter’s tip?
Shoulder is adducted
Elbow is extended and pronated
Wrist is flexed
What is affected in klumpke’s palsy?
Small muscles of the hand
What is the main presentation of Klumpke’s palsy?
Claw hand
Which cord of the brachial plexus does the musculocutaneous nerve come from?
Lateral cord
What spinal roots make up the musculocutaneous nerve?
C5,6,7
What muscles are innervated by the musculocutaneous nerve?
Coracobrachialis
Biceps brachi
Brachialis
What nerve is the elbow joint supplied by?
Musculocutaneous nerve
What is Hilton’s law?
A sensory nerve supplying a JOINT also supplies the MUSCLES moving the joint and the SKIN overlying the insertions of the muscles
What are the spinal roots of the axillary nerve?
C5,6
What muscles are supplied by the axillary nerve?
Deltoid
Teres minor
What trauma can cause axillary nerve palsy?
Shoulder dislocation
Fracture of surgical neck of humerus
What is clinical presentation of axillary nerve palsy?
Loss of sensation over badge area
Deltoid atrophy
What are the spinal roots of the radial nerve?
C5,6,7,8,T1
What can cause radial nerve palsy?
Entrapment
Compression
What do radial nerve palsy symptoms depend on?
The site of the lesion
What are symptoms of radial nerve palsy in the axilla?
Loss of elbow extension, wrist extension
Sensory changes in forearm and hand
What are symptoms of radial nerve palsy in the arm?
Loss of wrist extension and sensory loss
What are symptoms of radial nerve palsy in the forearm?
Loss of finger extension
What are symptoms of radial nerve palsy in the wrist?
Loss of sensation
What are the spinal roots of the median nerve?
C5,6,7,8,T1
What forms the carpal tunnel?
Floor - carpal bones
Roof - flexor retinaculum
What is found in the carpal tunnel?
Flexor digitorum superficialis x4
Flexor digitorum profundis x4
Flexor pollicis longus
Median nerve
What can cause carpal tunnel syndrome?
Developmental Trauma Swellings Inflammatory Metabolic
What are clinical features of carpal tunnel syndrome?
Nocturnal pain
Paraesthesia in part or all of median nerve distribution
Wasting of thenar muscles
What are nerve roots of the ulnar nerve?
C8,T1
What is the cubital tunnel?
Between medial epicondyle and olecranon with fascial bands as roof
What are symptoms of cubital tunnel syndrome?
Numbness on ulnar side of hand
Difficulty with fine tasks
Wasting of muscles in first webspace with hypothenar wasting
What is the main nerve of the sacral plexus?
Sciatic nerve
What are the branches of the sciatic nerve?
Common peroneal nerve
Tibial nerve
What is the main nerve of the lumbar plexus?
Femoral nerve
What muscles are supplied by the superior gluteal nerve?
Gluteus medius
Gluteus minimus
Tensor faciae latae
What muscle is supplied by the inferior gluteal nerve?
Gluteus maximus
What parts of the lower limb are supplied by the sciatic nerve?
Posterior thigh
Leg
Foot
What are spinal roots of the sciatic nerve?
L4,5,S1,2,3
What is the common peroneal nerve?
Branch of the sciatic nerve
Divides into the deep peroneal nerve and superficial peroneal nerve
Deep peroneal nerve supplies anterier compartment of leg
Superficial peroneal nerve supplies lateral compartment of leg
What are the main branches of the lumbar plexus?
Lateral femoral cutaneous nerve
Femoral nerve
Obturator nerve
