Lower Limb Neurological Examination

TO START

W2I2P4E

• Wash your hands

• Wear appropriate PPE

• Introduce yourself and check patient’s Identity

• Permission: “May I examine your arms?”

• Privacy: Ensure curtains to the bay are closed

• Pain: “Are you in any pain at all?” 

• Position: Patient sitting to begin, then lying

• Exposure: Both legs exposed, hips to toes with underwear on

INSPECTION

Surroundings

• As for upper limb exam

• Catheter bag - can indicate spinal problems

• Mobility aids, wheelchair

Patient

• As for upper limb exam - wasting, fasciculations, abnormal movements

SCREENING TESTS

Gait

• Ask the patient to walk the length of the room, turn and walk back

• Parkinsonian gait - hesitation starting, shuffling, freezing, decreased arm swing

• Ataxic gait - broad-based, unsteady

• Hemiplegic - flexors are weaker than extensors in lower limb resulting in an extended leg and characteristic gait whereby the leg is swung out in a lateral arc on taking a step

• Spastic - scissoring gait, eg cerebral palsy 

Heel-toe walking

• Ask the patient to walk ‘heel-to-toe’ for several steps, inability to do so is a sign of cerebellar or sensory ataxia

Romberg’s test

• Do not attempt if the patient is already unstable 

• Ask the the patient to stand with their back facing the couch (with their legs against the couch, in case of instability) and to stand with their feet together - unsteady in cerebellar disease

• If stable, with some reassurance, ask them to close their eyes - falling without correction is positive Romberg’s sign and indicates sensory ataxia (proprioceptive or vestibular dysfunction) 

TONE

Assessment

• Assess the tone in both hips, knees and ankles

• Ask the patient to relax and position them lying supine on the couch

• ‘Pastry roll’ each leg, watching to see the ankle lagging behind the leg rolling - increased tone if no lag

• Lift the knee suddenly - increased tone if the heel lifts off the couch

• Ankle clonus - partially flex the knee and support the leg to allow the patient to relax, dorsiflex the ankle and hold it in this position to test for clonus

• Clonus is a series of involuntary rhythmic contractions and relaxations - indicates UMN lesion of descending motor pathways

POWER

Notes

• Assess power for individual muscles as described below, isolate each joint and examine each side separately assessing like for like

• Use the MRC power scale to grade each muscle

• Remember to use appropriate force - the lower limb is more powerful than the upper limb!

Hips

• Test hip flexion and extension on each leg

• Ask the patient to straight leg raise and push into your hand

• Ask the patient to push their leg down towards the couch into your hand

Knees

• Assess knee flexion and extension on each leg

• Ask the patient to bend their knees resting their feet on the couch

• Ask the patient to ‘kick out’ against your hand

• Ask the patient to pull their heel up towards their bum, against the resistance of your hand on their calf

Ankles

• Assess ankle dorsiflexion and plantarflexion against the resistance of your hand

Big toe

• Assess big toe extension

MOVEMENT

MUSCLE

ROOT

NERVE

Hip flexion

Iliopsoas

L1, 2

Femoral

Hip extension

Gluteus maximus

L5, S1

Inferior gluteal

Knee extension

Quadriceps

L3, L4

Femoral

Knee flexion

Hamstrings

S1

Sciatic

Ankle dorsiflexion

Tibialis anterior

L4

Deep peroneal

Ankle plantarflexion

Gastrocnemius

S1, S2

Tibial

Big toe extension

Extensor hallucis longus

L5

Deep peroneal 

REFLEXES

Notes

• Test the knee-jerk, ankle-jerk and plantar reflexes 

• Ask the patient to completely relax

• Watch to see the muscle belly contract to confirm presence of the reflex

• Compare like for like 

• Try a reinforcement manoeuvre (eg ask patient to clench their jaw as you tap the tendon) if unable to elicit the reflex 

Knee-jerk (L3,4)

• Bend the patient’s knee and support the weight of their leg from behind the knee (or ask the patient to sit on the edge of the couch with their legs hanging over)

• Locate the patella tendon (inferior to the patella) and tap with the tendon hammer

• Observe knee extension and contraction of quadriceps 

Ankle-jerk (S1,2)

• Position the patient supine with the hip slightly abducted, knee flexed and ankle dorsiflexed

• Tap the achilles tendon with the tendon hammer

• Observe for plantarflexion of the ankle and gastrocnemius contraction

• This reflex can be difficult to elicit and can be easier with the patient  kneeling on a chair

Plantar/Babinski (L5, S1)

• Warn the patient that you are about to gently scratch the sole of their foot

• Run a blunt object along the lateral aspect of the foot curving towards the big toe

• Observe the big toe flex (normal), big toe extension and fanning of the other toes signifies an UMN lesion

COORDINATION 

Notes

• Tests cerebellar function

Heel-shin test

• Assesses for dysmetria

• Ask the patient to run the heel of their foot along the other shin to their foot and then raise their foot to reach your hand and repeat

Dysdiadochokinesia

• Ask the patient to rapidly tap each foot alternately on your hand as fast as they can

• Assess for dysdiadochokinesia as explained for upper limb

SENSATION

Light touch

• Explain to the patient that you are going to test the sensation in their legs and will require them to close their eyes

• Ask the patient to confirm when you are touching their left or right side, and whether it feels the same on both sides

• Start by confirming normal sensation at the patient’s sternum

• Ideally, assess with cotton wool (if unavailable - your fingertip)

• Assess each dermatome on each side, also assess for ‘glove and stocking’ sensory changes assessing distally to proximally 

• Consider testing vibration sense using a 128Hz tuning fork on bony prominences and pain sensation using a neurotip (spinothalamic tracts)

Proprioception

• Assess proprioception as described in the upper limb exam on the big toe of each foot

CLOSURE 

Closure

• Thank the patient, ensure they are comfortable and dressed. 

• Remove PPE

• Clean equipment and wash hands

To complete

• Full neurological examination (upper limb, cranial nerves)

• Consider other neurological exams

• Consider imaging (CT, MRI)

UMN

LMN

Inspection

No wasting or fasciculation (may have disuse atrophy)

Wasting and fasciculations

Tone

Increased (spasticity or rigidity), +/- ankle clonus

Decreased/normal

Reflexes

Brisk

Reduced/absent

Plantar reflexes

Upgoing/Babinski +

Normal

SCORE

DESCRIPTION

0

No contraction

1

Flicker of contraction

2

Movement with gravity eliminated

3

Movement against gravity

4

Movement against resistance

5

Normal power