Peripheral Nerve : Lower Limb (exam) Flashcards
For a lower limb PNS what are you looking for on general observation?
SWIFT
- symmetry
- muscle wasting
- Involuntary movements
- fasiculations
- tremors
Bedside:
mobility aids
What is the general layout of a lower limb PNS exam?
- WIPE (wash hands, intro, pt details, explain/consent)
- ask if in pain
- Gen inspection
- tone
- power
- coordination
- reflexes
- sensation
- end pieces
How do you asses tone in a lower limb PNS exam?
1) roll each leg (observe foot movement to see if increases or reduction in tone)
2) Passively flex and extend knee and ankle
what is clasp knife spasticity?
Clasp knife spacticity is increased tone caused by upper motor neurone disorders.
- it is initial resistance, followed by sudden reduction in resistance to movement
What is “initial resistance followed by sudden reduction in resistance to movement”
Clasp knife spasticity .
This is increased tone caused by upper motor neurone disorders
What is “lead pipe” rigidity/
In disorders of the basal ganglia “lead pipe” rigidity is detected due to sustained resistance throughout range of movement
What is sustained resistance throught range of movement known as? and what causes it?
“lead pipe” rigidity caused by basal ganglia disorders
What is “cog wheel” rigidity
“cog wheele” rigidity occurs in parkinson’s disease because tremor is superimposed in the underlying lead pipe rigidity
What is tremor superimposed on underlying lead pipe rigidity also known as? what causes it?
“cog wheel” rigidity caused by parkinsons
what is decreased tone caused by?
- lower motor neurone
Or - cerebellar lesion
How is power tested in the lower limb PNS>
- Test each muscle group, 1st patient does movement, then against resistance*
1) Hip flexion, extension, abduction, adduction
2) Knee flexion/extension
3) Ankle dorsiflexion and plantarflexion
4) Big toe flexion/extension
What is involved when testing co-ordination in the lower limb PNS?
1) Heel -shin test
2) Toe tapping
What reflexes are tested in the lower limb PNS exam and what are the nerve roots associated with each?
1) Patella (L3/4)
2) Ankle jerk (S1/S2)
3) Plantar /
4) Babinski reflex ( support ankle, scratch sole from lateral side of heel up and across base of toes.)
- normal big toe will flex
- abnormal big to extend - UMNL
5) Clonus (suddenly dorsiflex ankle, hold in position. Clonus is when foot flaps rhythimically - in upper motor neurone lesion)
What is an abnormal babinski reflex and what does this signify?
normal - big toe flex
abnormal - big toe extend. this is a sign of an upper motor neuron lesion.
What is a clonus ?
- suddenly dorsiflex ankle, hold in position. on release foot will move back and forth.
It is a sign of upper motor neurone lesion.
How is sensation tested in lower limb PNS?
1) test for light touch and sharp touch - compare dermatomes on both sides
How is proprioception tested in lower limb PNS?
1) pt close eyes
2) move big toe up and down, explain movement
3) move toe, pt identifies direction 3X
4) if they can’t identify movement , then do the same with proximal joint.
How is vibration sensation tested in lower limb PNS?
Use 128hz tuning fork on sternum.
then pt close eyes
use fork on big toe joint.
say when vibration starts and stops.
*If cant identify then move to proximal joint
What end pieces are relevant for lower limb PNS?
1) Romberg test
(pt stand with eyes closed, and feet together)
If they become unsteady then they have positive rombergs test.
- if unsteady with eyes open - then cerebellar lesion
- if unsteady with eyes closed then sensory ataxia
2) Gait
- parkinsons shuffle
- broad base gait (cerebellar lesion)
- high step gait (foot drop)
How would you explain and gain consent for a lower limb peripheral exam?
WIPE
Wash hands
Introduce Self - “hello, my name is ….., I’m a 3rd year medical student”
Patient details - “Can I start by checking your name, age and date of birth”
Explain - “Today I’ve been asked to do an examination of the nerves in your legs.
It will involve testing the co-ordination, reflexes and sensation in your legs.
You’ll have to be exposed from the waist down,
and the examiner will act as a chaperone today
- Is this ok with you?
