Lower Limb Neuro Exam Flashcards
What are some upper motor neurone signs?
- Hypertonicity (spasticity)
- “Pyramidal” pattern of weakness
- Hyper-reflexia
- Ankle clonus
- Babinski positive
Potentially:
- Disuse atrophy
What are some lower motor neurone signs?
- Muscle wasting
- Fasciculations
- Hypotonia
- Varying patterns of weakness
- Hyporeflexia or areflexia
- Normal or absent planter reflex
What around the bed may suggest neurological problems?
- Wheelchair
- Walking aids
- Catheter
What menmonic can help with a neuro visual inspection?
A SWIFT
What does the mnemonic A SWIFT mean?
A - Asymmetry
S - Scars
W - Wasting
I - Involuntary movements
F - Fasciculations
T - Tremor
What are some involuntary movements to look for in neuro inspection?
- Dystonia
- Chorea
- Myoclonus
- Athetosis
- (Fasciculations)
- (Tremor)
What is an important distinction to make about tremors?
Resting vs Kinetic
Involuntary sustained or intermittent muscle contractions cause twisting and repetitive movements, abnormal postures, or both
Dystonia
Random-appearing sequence of one or more discrete involuntary movements
Chorea
Slow, continuous, involuntary writhing movements often affecting the extremities
Athetosis
Repeated, often non-rhythmic, brief shock-like jerks due to sudden involuntary contraction or relaxation of one or more muscles
Myoclonus
Rhythmic back-and-forth or oscillating involuntary movement about a joint axis
Tremor
Give 2 causes of dystonia
- Parkinson’s Disease
- Dyskinetic Cerebral Palsy
Give 2 causes of chorea
- Dyskinetic Cerebral Palsy
- Huntington’s Disease
Give 2 causes of athetosis
- Dyskinetic Cerebral Palsy
- Huntington’s Disease
Give a cause of myoclonus
Myoclonic epilepsy
What is a common cause of resting tremor?
Parkinson’s Disease
What is a common cause of a kinetic tremor?
Benign essential tremor
When inspecting a patient in a neuro exam, what clues may be seen in the face?
- Hypomimia
- Ptosis
- Ophtalmoplegia
What is hypomimia?
Lack of facial expression
What is a common cause of hypomimia?
Parkinson’s Disease
What systemic neurological condition can cause ptosis and ophthalmoplegia?
Myasthenia gravis
What is shown here?
Muscle wasting
What function should be tested first in a lower limb neuro exam?
Gait
How is gait assessed?
- Back and forth walking
- Heel-to-toe walking
What are some abnormal types of gate?
- Ataxic
- Parkinsonian
- High-stepping
- Waddling
- Hemiparetic
- Spastic paraperesis
What are the features of an ataxic gait?
- Broad based
- Unsteady
- Unable to heel-toe walk
What are the potential causes of an ataxic gait?
- Cerebellar lesion
- Sensory ataxia (proprioceptive loss)
What can differentiate a sensory ataxic gait from a cerebellar gait?
In a sensory ataxic gait they may stare intensely at their feet to make up for loss of proprioception
What are the features of a parkinsonian gait?
- Shuffling steps
- Stooped posture
- Reduced arm swing
- Several steps to turn
What is a high stepping gait?
Lifts one (or both) feet high to compensate for foot drop
What causes foot drop?
Weakness of ankle dorsiflexion
What is the most common cause of weak ankle dorsiflexion?
Peroneal nerve injury
What are the features of a high-stepping gait?
- Shoulders sway side-to-side
- Legs lifted off by tilting the trunk
What causes a waddling gait?
Weakness of the pelvic girdle muscles
What are the features of a hemiparetic (and spastic paraparetic) gait?
- Stiff legs
- Circumduction
- -
- (Bilateral and scissoring of feet)
What is circumduction of the legs when walking?
Swinging them in an arc with each stride
What is scissoring of the feet?
Inverted feet
What sort of lesion causes a hemiparetic or paraparetic gait?
UMN lesion
What is a common cause of hemiparetic or paraparetic gait?
Cerebral palsy
What disorders can cause problems with heel-toe walking?
- Proprioception impairment
- Cerebellar disorder
What test shoudl be performed after gait?
Romberg’s Test
How is Romberg’s test performed?
- Ask the patient to stand with feet together and eyes closed
- Place arms front and back of patient to reduce sway in a positive test
- Obsever for excessive swaying for 10 ~seconds (1 min is ideal but come on this is an OSCE)
What is a positive Romberg’s test?
Swaying or falling over
What does a positive Romberg’s test suggest?
Sensory ataxia (loss of proprioceptive deficit)
How is tone assessed in the lower limb?
- Ask the patient to let their legs go floppy
- Rolling the leg (tests hips)
- Leg lift at the knee (heel should remain in the bed)
- Move the foot at the ankle
- Quadriceps and calf clonus
What is clonus?
Rapid sustained jerking upon forced stretching of the muscles
How is quadriceps clonus elicited?
Rapidly push the quads down towards the knee
How is calf muscle clonus elicited?
Rapid dorsiflexion of the ankle
How should power be assessed in the lower limbs?
- Assess each function one side at a time, comparing like for like
- Stabilise limb to isolate the joint if needed
- Use MRC muscle power assessment scale
Power in which joints should be assessed in a lower limb neuro exam?
- Hip
- Knee
- Ankle
- Big toe
Power of which hip motions should be tested in a neuro exam?
- Flexion
- Extension
- Abduction
- Adduction
What nerve roots provide power to hip flexion?
L1/2
What nerve roots provide power to hip extension?
L4/S1
What nerve roots provide power to hip abduction?
L4/5
What nerve roots provide power to hip adduction?
L2/3
Power of which knee movements should be tested in a lower limb neuro exam?
- Flexion
- Extension
What nerve roots provide power to knee flexion?
S1
What nerve roots provide power to knee extension?
L3/4
Power of which ankle movements should be tested?
- Dorsiflexion
- Plantarflexion
What nerve roots provide power to ankle dorsiflexion?
L4
What nerve roots provide power to ankle plantarflexion?
S1/2
Power of which big toe movement should be tested in a lower limb neuro exam?
Extension
What nerve roots provide power to big toe extension?
L5
Which deep tendon reflexes should be tested in a lower limb neuro exam?
- Knee jerk
- Ankle jerk
- Plantar reflex (not really tendon)
*
What nerve root supplies the knee jerk reflex?
L3/4
What nerve root supplies the ankle jerk reflex?
L5/S1
What nerve root supplies the plantar reflex?
S1
How should tendon reflexes be tested?
- Ensure patient’s limb is completely relaxed
- Hold hammer at end and use gravity to aim a good swing at the tendon
- Observe for absent or exaggerated reflexes
How is the knee jerk tested?
How is the ankle jerk reflex tested?
How is plantar reflex tested?
- Run a blunt object along the lateral edge of the sole of the foot, moving towards the little toe, then medially under the toes
- Observe the great toe
What is a normal plantar reflex?
Flexion of the great toe and other toes
What is an abnormal plantar reflex?
Extension of the big toe and spreading of the others
What is an abnormal plantar reflex also known as?
Positive Babinski sign
What does a positive Babinksi sign indicate?
UMN lesion
If a reflex is absent, what should you ask the patient to do?
Clench their teeth and try again
What sensory modalities should be tested in the upper limbs?
- Pin prick
- Light touch
- Proprioception
- Vibration
Which tested sensory modality(s) are carried by the spinothalamic tracts?
Pin prick
Which tested sensory modality(s) are carried by the dorsal columns?
- Light touch
- Proprioception
- Vibration
What should be used to assess light touch sensation?
A wisp of cotton wool
What should be used to assess pin-prick sensation?
Sharp end of a neuro tip
How should light touch and pin-prick sensation be tested?
- Demonstrate sensation on the sternum
- Ask the patient to close their eyes
- Assess each dermatome in turn
- Ask patient to say yes when touched
- Compare left to right and ask for any differences
- Assess distal sensation at the tips of the big and little toes, move more proximally gradually until sensation is identified
What are some common distributions of sensory loss?
- Dermatomal
- Glove🧤 (and stocking)🧦
- Loss of all sensation below a certain level
- (Brown-Sequard syndrome)
*
What does a glove and stocking distribution of sensory loss commonly suggest?
Peripheral neuropathy
Is glove and stocking distribution usually symmetrical or asymmetrical?
Symmetrical
What does a dermatomal sensory loss suggest?
Radiculopathy (compression of the nerve root)
What commonly causes complete loss of sensation below a certain level?
Complete cord transection
What should be used to test vibration sensation?
128 Hz tuning fork
How should vibration sense be tested?
- Tap tuning fork
- Place on sternum to confirm feeling
- Ask patient to close their eyes
- Place on distal phalanx and ask if they can feel vibration and when it stops
- If not felt move to the next most proximal joint (if felt can leave it there)
- Compare both sides
How should proprioception be tested?
- Demosntrate movement of the distal phalanx upwards and downwards with the patient watching
- Ask patient to close their eyes
- Ask them to identify the position of the big toe as you move it
- If unable to do so, move more proximally
How is co-ordination assessed in the lower limb?
Heel to shin test
How is the heel to shin test performed?
- Ask patient to put their heel on the opposite knee
- Run heel down shin towards foot
- Repeat this numerous times
- Perform on both sides
What can cause an inability to perform heel to shin test?
- Cerebellar disorder
- Loss of motor strength
- Loss of proprioception
How should a lower limb neuro exam be completed?
- Thank patient
- Wash hands
- Summarise findings
What further investigations/examinations can be performed following an upper limb neuro exam?
- Cranial nerve examination
- Upper limb neuro examination
- Imaging e.g. CT/MRI if required
Which region is innervated by T12-L1?
Inguinal/groin region
Which region is innervated by L2?
Lateral and anterior thigh
Which region is innervated by L3?
Medial thigh and anterior knee
Which region is innervated by L4?
Medial leg
Which region is innervated by L5?
Lateral leg and medial foot
Which region is innervated by S1?
Lateral foot (including digits 4 and 5) and heel and Achilles’ tendon
Which region is innervated by S2?
Posterior thigh, popliteal fossa and central triangle moving halfway down leg
Which region is innervated by S3?
Outer buttock
Which region is innervated by S4?
Inner buttock
Which region is innervated by S5?
Ring around anus
What sort of gait is shown here?
Parkinsonian
What sort of gait is shown here?
Ataxic (on heel-toe walking)
What gait is shown here?
Hemiparetic gait with circumduction
What sort of gait is shown here?
Waddling gait
