EXAMINATION OF THE CENTRAL NERVOUS SYSTEM

1. CNS Examination

2. Aspects of Examination
1. General Ex
2. The Cranial nerves
3. The upper limbs
( Motor + Sensory + coordenation )
4. The lower limbs
( Motor + Sensory + coordenation)
5. The skull and spine for local disease
6. The carotid arteries for bruits

3. General Examination
• Assessment of the higher centers
• Speech
• Neck stiffness
• Abnormal movements

4. General Examination
1. Assessment of the higher centers
o Consciousness
o Orientation ( Person , Place , Time ).
o Memory
o Handedness
2. Speech
o Flow of speech
o Comprehension
o Repetition

5. 3. Neck stiffness
looking for meningism ( meningitis ,SAH)

6. Cranial Nerves Examination
• you have to know how to examine all cranial
nerves in detail but we will focus on the most
important ones ( 3rd , 4th , 5th , 6th , 7th , 11th &
12th ) .

7. Where CN Come From?
• 3rd & 4th cranial nerves are located in the mid brain
• 5th , 6th , 7th & 8th cranial nerves are located in the
pons
• 9th , 10th , 11th & 12th cranial nerves are located in the
medulla oblongata

8. CN III, IV, VI: Oculomotor, Trochlear,
Abducent
• Inspection of pupil
• Light reflex
• Eye Movement & nystagmus
• Convergence & accomodation

9. • Look at pupils: shape, relative size,
• Ptosis.
• Shine light in from the side to look for pupil's light
reaction.
• Assess both direct and consensual
responses.
• Assess afferent pupillary defect by moving light
in arc from pupil to pupil.

10. The pupils

12. CN V :Trigeminal
• Motor
• Sensory
• Reflex

13. • Motor :pt opens mouth, clenches teeth )pterygoids).
• Palpate temporal, masseter muscles as they clench .
• Jaw jerk :
– Dr's finger on tip of jaw .
– Grip patellar hammer halfway up shaft and tap Dr's finger
lightly.

14. • Sensory
Facial sensation by cotton on forehead, cheek
& jaw.

15. • Corneal reflex :patient looks up and away.
• Touch cotton wool to other side.
• Look for blink in both eyes, ask if can sense
it.
• Repeat other side [ tests V sensory, VII
motor].

16. CN VII :Facial
• Motor
• Taste sensation

17. CN VII :Facial
• Inspect for facial droop or asymmetry .
• Facial expression muscles :pt looks up
and wrinkles forehead.
• looking for wrinkling loss.
• Pt shuts eyes tightly :compare each side .

18. • Pt smile :compare nasolabial grooves .
• Pt show teeth, puff out cheeks .
• Taste sensation in the anterior 2/3 of the
tongue.

20. CN XI: Accessory
• Inspection From behind, examine for trapezius
atrophy, asymmetry.
• Pt. shrugs shoulders (trapezius).
• Pt. turns head against resistance: watch,
palpate SCM on opposite side.

21. CN XII: Hypoglossal
• Inspect tongue in mouth for wasting,
fasciculations.
• Protrude tongue: unilateraldeviates to
affected side.

23. Motor system
don’t forget to compare both limbs
• Inspection
• Palpation ( muscle bulk + tenderness )
• Muscle tone
• Muscle power
• Reflexes

24. Motor system
1. Upper limbs (compare)
• Inspect for muscle wasting ( proximal &
Distal ) – scars – deformity – fasciculation –
skin pigmentation.
• Drift test

25. • Feel the muscle bulk ( proximally & Distally ) –
muscle tenderness.
• Tone ( normo – hypo – hypertonia )
by passive movement of wrist and elbow
joints.

26. • Power ( 0 – 5 )
by active movement at the shoulder , elbow ,
wrists and fingers.

27. • Reflexes ( 0 - ++++ )
Biceps ( C5,C6 ) – Triceps ( C7,C8 ) –
Brachioradialis ( C5,C6 )

28. • Coordination
Finger to nose test
Finger to finger test
Dysdiadochokinesis
Rebound test

29. 2. Lower limbs
• Inspect the gait of the patient
• Expose both thighs and legs.
• Inspect for muscle wasting – scars – deformity –
posture -fasciculation – skin pigmentation .

30. • Feel the muscle bulk and muscles for
tenderness.
• Tone ( normo – hypo – hypertonia )
by passive movement of the knee and ankle
joints

31. • Clonus more than 3
ankle and knee clonus
• Power ( 0 – 5 )
by active movement at the hip , knee , ankle ,
and tarsal joints

32. • Reflexes ( 0 - ++++ )
Knee jerk ( L3,L4 ) – Ankle jerk (S1,S2 ) – Plantar reflex
( L5, S1 , S2 )
• Coordination
Heal to shin test . Toe finger test
Foot Tapping test

33. Sensory system
• Spinothalamic pathway
Pain and Temperature ( usually temperature is not tested )
• Posterior column pathway
Vibration and Proprioception
Romberg Sign
• Light touch with cotton wool

34. Back
• Inspect for deformity – scars – neurofibromas .
• Palpate for tenderness over the vertebral bodies
• Do the straight leg raising test

36. Auscultation
• Auscultate over the carotid arteries looking for
bruits.

37. Thank you