Peripheral Neuroanatomy II Flashcards
What is the most common cause of lumbar radiculopathy?
comression of nerve root by a herniated intervertebral disc (nucleus pulposis)
most common site is disc between L5-S1 (L4-5 next, then L3-4). Lateral disc most likely to herniate, so most likely to effect theroot that exist BELOW the disc (S1 most common for L5-S1 herniation)
L4 radiculopathy: clinical presentation
anterior thigh and medial calf pain and sensory loss. quadriceps weakness. decr. knee jerk reflex.
L5 radiculopathy: clinical presentation
Pain: posterior thigh, lateral calf, dorsum of foot pain
sensory loss to lateral calf, great toe
motor loss to dorsiflexors and evertors, EHL (extensor hallicus longus- helps with eversion and dorsiflexion and big toe extension)
No reflex loss
S1 radiculopathy: clinical presentation
pain: posterior thigh and calf, sole of foot
sensory loss to posterior calf, lateral foot
motor loss to plantar flexors and invertors
ankle jerk loss
What is diabetic amyotrophy: clinical features. etiology, treatment
seen in pts with diabetes mellitus
pain in thigh
weakness and numbness of thigh and leg
absent knee jerk
from infarction of vasa nervorum supply lumbosacral plexus
treat with time
Common problem with lateral femoral cutaneous nerve.
meralgia paresthetica
sensory only to anterolateral thigh
symptoms: pain and paresthesias
from tight belts: constriction at inguinal ligament, obesity
treatment: remove constriction, amitriptyline (antidepressant?)
What are the clinical features of femoral nerve problems? Etiology? differential diagnosis?
Motor: probs with psoas, qudriceps femoris
Sensory to anteromedial thigh, anteromedial leg (saphonous nerve)
can be from hemotoma, abscess, tumor, trauma (including delivery?), lymph node problems
DD: include L2,3,4 radiculopathies
What are clinical features of obturator nerve problems? Etiology?
motor: problems with hip adduction
sensory: medial thigh
etiology: often prolonged labor
What are the clinical features of sciatic nerve problems? What should I know about the sciatic nerve?
this nerve divides into the peroneal (aka fibular) and tibial nerves just above the knee
motor: hamstrings, all muscles of leg and foot
sensory: posterolateral leg and the entire foot
What is sciatica?
lower limb pain that radiates in the distribution of the sciatic nerve. usually due to L4-S2 radiculopathy rather than compression of the sciatic nerve itself
patients may say they have “hip pain-“ but pain is in the butt, not the hip.
If I learn of injury to the sciatic nerve, what should be on my DD?
IM injections
tumors
What does the deep branch of the peroneal/fibular nerve do?
Motor: ankle dorsiflexors
sensory: to 1st web space
What does the superficial branch of the peroneal/fibular nerve do?
ankle eversion
sensory to lateral leg
What are the clinical features of peroneal/fibular nerve palsy? What is the etiology?
foot drop from weakness of dorsiflexion and eversion
sensoty: lateral leg for superfical and 1st web space for deep
From leg crossing, extreme weight loss (that allows for leg crossing), compression at the fibular head)
What else is on the DD for peroneal/fibular nerve palsy? How do you distinguish?
L5 radiculopathy, which can also cause foot drop from dorsiflexion. L5 radiculopathies should show problems with inversion as well as eversion, though (maybe a little? though most of inversion is S1, right?)
