 |
What's
involved:
|
|
Location:
 |
Lateral
Cutaneaous
Nerve
of
Thigh
in
the
upper
and
outer
thigh
|
|
|
Common
symptoms:
|
Pain,
burning in the thigh
|
|
Poor
tolerance to touch, clothes, cover or anything that rubs against thigh
|
|
In mothers
(or fathers) pain/burning with children sitting on lap
|
|
No thigh or
leg weakness or atrophy
|
|
Usually
unilateral
|
| Symptoms always present, no
night/day preference
|
|
| Onset:
|
Usually
Gradual over days, weeks
|
| May be Sudden
|
|
|
Risk factors:
|
No gender
preference
|
|
Diabetes or
family history of Diabetes, Alcoholism or other occupational or
nutritional causes of Neuropathies, HIV infection
|
|
Overweight
|
| Tight undergarments or
clothing in the inguinal area
|
|
|
Exam:
|
Decreased
sensation over upper and lateral area of thigh
|
|
Sometimes
decreased sensation all the way to the patella
|
|
Difficult
to examine because of pain/burning induced by touching or rubbing
|
|
Normal
strength, no atrophy
in thigh muscles
|
| Preserved Knee Jerk (if
absent or unilaterally decreased suspect L3 root lesion)
|
|
| Localization:
|
Pure
sensory
branch
involvement
at
the
upper
and
lateral
end
of
the
inguinal
ligament
|
|
|
EMG:
|
Study
Lateral Cutaneous Nerve of Thigh, usually small amplitude (<10
microVolts)
|
|
Study both
sides to compare amplitudes
|
|
Response
may be absent or significantly (<50%) smaller than healthy side
|
|
Nerve
Conductions may be difficult
to perform in overweight people
|
| Rule out L3 root lesion by
studying other Femoral and non-Femoral innervated muscles to include:
|
|
In Meralgia
Paresthetica, the needle exam of the Thigh muscles will be normal
|
|
In L3 root
lesions, Vastus Lateralis, Ilio-Psoas, Thigh Adductors and/or paraspinals
could be involved
|
|
In Femoral
Nerve lesions, Vastus Lateralis and Ilio-Psoas, but not Thigh Adductors,
are involved
|
| In Obturator Neuropathy, only
Thigh Adductors are involved
|
|
| Recommendations:
|
Can be very
annoying
|
|
Symptomatic
treatment
|
|
Stop/decrease
cause, tight undergarments, clothing
|
|
Lose weight
|
|
Dilantin,
Neurontin, Elavil have been tried with various degrees of success
|
| Injections
|
|
|
What else
could it be:
|
Could be an
L3 root lesion if associated muscle weakness (Vastus Lateralis, Ilio-Psoas and/or
Thigh adductors) or absent or unilaterally decreased Knee jerk
|
| Few other conditions can
cause the same symptoms
|
|
