Peripheral nerve examination

Question 1

Neurological examination

Answer 1

General inspection:
– observe pt (SWIFT, scars, wasting, involuntary movement, fausiculations and tremor), look at their stance and gait

coordination- testing and observation

movement and power- myotomes

Reflexes- deep tendon and superficial

Sensory testing- dermatomes and positional testing

Question 2

Observing gait and coordination

Answer 2

Stance

Testing gait- normal walk and Tandem gait (get them to walk like they are on a tight rope)

Romberg’s sign:
– get pt to stand with legs closed together and raise arms in their air with their eyes closed
– aim to hold this for 30 seconds if possible and maybe even 60 seconds
—- can assess pronator drift as when their hands are infront of them, their arms may start to pronate (can be one or both arms)

Coordination:
– finger to nose test (depth perception)
– heel to shin test
– dysiadochokinesis

Question 3

Different types of gait and what they might mean

Answer 3

Waddling gait- developmental dysplasia

Spastic gait (foot dragging across the floor, causing by a long muscle contraction on one side)- cerebral palsy

Shuffling gait- parkinsons

Steppage gait (foot drop while walking)- spinal injury, parkinsons, MS

Scissor gait (knees turned inwards like the shape of scissors)- brain tumour, MS and cerebral palsy

Question 4

Assessing tone

Answer 4

Tone- the resistance to passive stretch

To assess tone, a very passive and gentle movement of the areas. If there is too much tone it will be stiff and difficult to move (like the pt is tensing their muscles)
– wrist- flex and extend
– elbow- flex and extend
– shoulder- adduct and abduct
– hips- log roll
– knee- flex and extend

How tone is graded:
0-4:
0- no response
1- hypotonicity (LMN)
2- normal
3- mild-moderate hypertonicity
4- severe hypertonicity (UMN)

Hypertonia can be spasticity or rigidity:
- spasticity:
— velocity dependant resistance to passive movement and is detected during quick movements. Is a feature of UMNL
—– cerebral palsy and multiple sclerosis

• Rigidity:
  — sustained resistance throughout the whole range of motion, and is detected when moving the limb slowly. Seen in parkinsons as a ‘lead-pipe rigidity’

Question 5

Clonus

Answer 5

Where the muscle will tense and jerk when moving it

Rhythmic series of contraction evoked by sudden stretch of the muscles

Clonus is typically seen in patients with an upper motor neuron lesion like- stroke, MS, cerebral palsy etc.

Question 6

Assessing myotomes

Answer 6

A muscle or group of muscles that is innervated by a single spinal nerve

When assessing get pt to perform movement first to show they can do it
Always palpate the muscle you are targeting aswell

UPPER:
C1-C2- flex and extend pts neck
C3- SB the cervical spine both sides
C4- shoulder elevation
C5- shoulder abduction
C6- flex elbow, wrist extension
C7- elbow extension, wrist flexion
C8- thumb extension, wrist ulnar deviation
T1- finger adduction and abduction

LOWER:
L2- hip flexion
L3- knee under pt’s, leg extension
L4- dorsi flexion and inversion
L5- big toe extension
S1- plantar flexion
S2- knee flexion

How myotomes are scored:
0-5- 5 is normal

0- absent (nerve is severed)
1- flicker but no movement
2- joint movement when gravity is eliminated (cant perform movement against gravity)
3- movement against gravity but not against resistance
4- movement against resistance but weaker than normal
5- normal

Question 7

Deep tendon reflexes

Answer 7

Tendon reflex- involuntary contraction of a muscle in response to stretch.

C5- biceps (get pt to flex their elbow to find the biceps tendon, and tap over your thumb)
— if there is no biceps jerk, but finger flexion occurs may suggest lesion at the C5/C6 nerve root

C6- brachioradialis (get pt to hammer curl their arms to find the brachioradialis tendon)

C7- triceps tendon

L4- patella tendon

S1- achilles tendon

How deep tendon reflexes are scored:
0-4- 2 is normal

0- absent (nerve severed)
1- hyporeflexia (LMN lesion)
2- normal
3- hyperreflexia (UMN lesion)
4- brisk/clonus

In healthy elderly people the ankle jerks may be reduced or lost.

Isolated loss of a reflex suggests mononeuropathy or radiculopathy.

A normal reflex contraction with delayed relaxation may occur in hypothyroidism.

Question 8

Superficial reflexes

Answer 8

Umbilical:
T8-T12- will be absent with a corticospinal lesion
—- run spiky end of the patella hammer over the pt’s umbilicus. If there’s no reflex to this, then this is not normal

Babinski’s:
L5-S1- usually accompanied with hyperreflexia, clonus and increased tone
—- run spiky end on the bottom of the feet, if the great toe extends on its own, then this is not normal

Question 9

Dermatome testing

Answer 9

Scored 0-2
0- absent
1- altered sensation
2- normal

Question 10

Vibration and joint position sense

Answer 10

Vibration sense:
Tests the dorsal column

This can be affected by diabetic neuropathy:
– vibration is one of the first senses to go when you have diabetes

Use a 128Hz tuning fork and place it over certain bony prominences and ask the pt to report if they dont feel the vibrations and if they do feel the vibrations

Lower limb:
– tip of great toe, interphalangeal joint, medial malleolus, tibial tuberosity and ASIS

Upper limb:
– DIP of forefinger, radial styloid process, olecranon and acromion

Joint position sense:
Also tests the dorsal column
– first demonstrate the procedure and show the pt what you are going to do
– with the pt’s eyes closed perform either plantar flexion or dorsi flexion and ask the pt to tell you what movement you are putting their foot into

Question 11

Meningeal irritation testing

Answer 11

Triad symptoms of meningitis:
– pyrexia (fever), nuchal rigidity (neck stiffness), headaches

L’hermittes sign- passive cervical spine flexion
+VE- shooting ‘electric’ pain radiating into the arms and legs
—- Brudzinski’s sign- legs and hip will flex up when cervical spine is flexed up

Kernig’s sign:
– flex hip to 90 degrees along with the knee, extend the knee.
+VE- resistance of pain

Question 12

The different tracts

Answer 12

Ascending:
- spinothalamic:
– anterior- crude touch (tickle, itch and pressure)
– lateral- pain and temperature (sharp pain, slow C fibres conduct dull and burning pain)

• spinocerebellar:
  – muscle spindle
  – Golgi tendon organ
  (myotomes, deep tendon reflexes)
• dorsal column:
  – conscious proprioception
  – vibration
  – fine touch
  – joint position sense
  (superficial reflexes, vibration sense and joint position sense)
  —- dorsal column can be affected by diabetes

Descending:
- pyramidal:
– conscious control of muscles from the cerebral cortex to the muscles of the body and face

• extra-pyramidal:
  – unconscious, reflexive or responsive control of muscles from various brainstem structures to postural or anti-gravity muscles
  —- reticulospinal, vestibulospinal, rubrospinal and tectospinal