1. Neurological/Sensory Assessment
Assist. Proff.
Dr.Sajeda Al-Chalabi
Head of Dept. of Physiology

2. The Sensory System
Examining the sensory system provides information regarding the integrity of the Spinothalamic Tract, posterior columns of the spinal cord and parietal lobes of the brain.
Diabetes mellitus, Folic acid deficiencies
Alcoholism and neurotoxin damage (e.g. insecticides) are the most common causes of sensory disturbances.

3. Neurological/Sensory Assessment
Tools: cotton, sharp object, coin, Test tubes with hot/cold water , tuning fork 128Hz&divider.

4. The sensory system Spinothalamic system : pain temperature light touch
Dorsal column pathway (proprioception): joint position
vibration
two point discrimination
graphaesthesia stereognosis

5. Sensory Function Superficial sensations: Light touch Pain Temperature
Deep sensations:
Vibratory sensations
Position sense
(Continued)

6. Sensory Function Discriminatory sensations: Stereognosis Graphesthesia
2 point discrimination

7. Compare each limb in the same position.
Light touch
Use the light touch of a finger, a piece of cotton wool or a piece of tissue paper.
It is important to touch and not to stroke, as a moving sensation, such as rubbing and scratching, is conducted along pain pathways.
Ask the patient to close his eyes and tell you when he feel you touching him.
Compare each limb in the same position.
A logical progression is required. You may want to start testing over the shoulder and to move along the lateral aspect of the arm and up the medial side.
Anesthesia = absent
Hypoesthesia = decreased
Hyperesthesia = increased

8. He should report areas of diminished pain sensation.
Using the pin, the patient is lightly pricked on the forehead or chest, to familiarize him with the sensation.
As above, the patient closes his eyes and counts when he perceives the sensation.
He should report areas of diminished pain sensation.
Analgesia = absence of pain sensation
Hypalgesia = decreased
Hyperalgesia = increased

9. Temperature
An easy and practical approach is to touch the patient with a tuning fork as the metal feels cold.
Compare the quality of temperature sensation on arms, face, trunk, hands, legs and feet.
Test tubes of warm(40-45°c and cool(5-10°c) water may be used for more accurate assessment. Ask the patient to distinguish between warm and cool on different areas of the skin with their eyes closed.

10. Joint position sense (proprioception).
Test at the distal interphalangeal joint of the index finger.
Hold the middle phalanx with one thumb and finger and hold the medial and lateral sides of the distal phalanx with the other. Move the distal phalanx up and down, showing the patient the movement first.
Ask the patient to close their eyes and move the distal phalanx up and down randomly. Ask the patient to tell you the direction of movement each time.
Test on both hands.
If there is an abnormality, move backwards to the proximal interphalangeal joint and so on until joint position sense is normal.

11. Use a 128 Hz tuning fork and ensure the tuning fork is vibrating.
Vibration
Use a 128 Hz tuning fork and ensure the tuning fork is vibrating.
Place it on the sternum to start with so that the patient can feel the sensation.
Then place it on one of the distal interphalangeal joints of one of the fingers.
If no vibration is sensed, move backwards to the metacarpophalangeal joint, the wrist, etc.
Asking the patient to tell you when the tuning fork stops vibrating can be helpful if there is doubt that their vibration sense is intact.

12. Two-point discrimination
Ask the patient to close his eyes.
Take the patient's index finger in one of your hands.
Using the discriminator(divider) or paper clip, touch the pulp of the finger with either one or two of the testing tips.
The patient must tell you whether they can feel one or two stimuli.
Find the minimum distance at which they can discriminate the two tips.
This distance is around mm in the finger pulps and 4-7cm on trunk.

13. Test stereognosis
by asking the patient to close their eyes and identify the object you place in their hand. Place a coin or pen in their hand. Repeat this with the other hand using a different object.
Astereognosis refers to the inability to recognize objects placed in the hand. Without a corresponding dorsal column system lesion, these abnormalities suggest a lesion in the sensory cortex of the parietal lobe.

14. Graphesthesia
Test graphesthesia by asking the patient to close their eyes and identify the number or letter you will write with the back of a pen on their palm. Repeat on the other hand with a different letter or number.

15. Joint position sense (proprioception)
Test at the interphalangeal joint of the big toe.
Hold the proximal phalanx with one thumb and finger and hold the medial and lateral sides of the distal phalanx with the other. Move the distal phalanx up and down, showing the patient the movement first.
Ask the patient to close their eyes and move the distal phalanx up and down randomly. Ask the patient to tell you the direction of movement each time.
Test on both feet.
If there is an abnormality, move backwards to the metatarsophalangeal joint and so on until joint position sense is normal.

16. Use a 128 Hz tuning fork and ensure the tuning fork is vibrating.
Vibration sense
Vibration sense
Use a 128 Hz tuning fork and ensure the tuning fork is vibrating.
Place it on the sternum to start with so that the patient can feel the sensation.
Then place it on the big toe.
If no vibration is sensed, move backwards to the bony malleolus of the ankle, the tibial shaft and tuberosity and the anterior iliac crest.
Asking the patient to tell you when the tuning fork stops vibrating can be helpful if there is doubt that their vibration sense is intact.

17. Examination of the sensory system
2-point discrimination
This test is not usually performed on the soles of the feet because the distinguishing distance is usually much greater than that on the finger.

18. Motor Function Finger-to-nose Heel-to-shin Rapid alternating movements
Romberg
Gait: heel-to-toe

19. Examination of co-ordination
The cerebellum helps in the co-ordination of voluntary, automatic and reflex movement. Tests of cerebellar function, however, are only valid if power and tone are normal, and that failure to perform them may also be related to power and tone abnormalities in the upper limb rather than a cerebellar problem. These include:
The finger-nose test:
The patient should keep their eyes open.
Hold one of your fingertips up in front of and a short distance (about cm) from the patient.
Ask the patient to touch the tip of their nose and then to touch your fingertip alternately and repeatedly. You can continuously change your fingertip position to make the test more difficult.
You can then test for sensory ataxia by asking the patient to close their eyes and to touch the tip of their nose using their outstretched finger.
Repeat these tests on the other side.
Look for intention tremor and past-pointing as the patient touches the examiner's fingertip, which can indicate disease of the cerebellar hemispheres.

20. Examination of co-ordination
The cerebellum helps in the co-ordination of voluntary, automatic and reflex movement. Tests of cerebellar function in the lower limbs require normal power, tone and sensation to be valid and include:
The heel-shin test:
Ask the patient to lift one of his legs and flex it at the knee, keeping the other leg straight.
He should then place the heel of the flexed leg on the knee of the other leg and run it down the shin towards the ankle and back again towards the knee.
Ask them to repeat this a number of times.

21. Romberg's test
also tests balance mechanisms that rely on the cerebellar, vestibular and proprioceptive systems.
Ask the patient to keep his eyes open and stand with his feet together, arms by their sides.
Then ask them to maintain this position when they close their eyes.
Patients who have cerebellar lesions often cannot stand in this position, even with their eyes open. If balance is only lost when the eyes are closed, this signifies a proprioceptive or vestibular lesion.
Be ready to catch the patient by standing behind.