CNS Examination

Done byDr/ Abdullah Mohd. Jan

MBBS,Intern

Aspects of Examination

1. General Ex2. The Cranial nerves3. The upper limbs ( Motor + Sensory + coordenation )4. The lower limbs ( Motor + Sensory + coordenation)5. The skull and spine for local disease6. The carotid arteries for bruits

General Examination

• Assessment of the higher centers

• Speech

• Neck stiffness

• Abnormal movements

General Examination

1. Assessment of the higher centers o Consciousness o Orientation ( Person , Place , Time ).o Memoryo Handedness

2. Speecho Flow of speecho Comprehensiono Repetition

3. Neck stiffness

looking for meningism ( meningitis ,SAH)

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 ) .

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

• Inspection of pupil

• Light reflex

• Eye Movement & nystagmus

• Convergence & accomodation

CN III, IV, VI: Oculomotor, Trochlear, Abducent

• 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. 

The pupils

• Motor

• Sensory

• Reflex

CN V: Trigeminal

• 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.

• Sensory Facial sensation by cotton on forehead,

cheek & jaw.

• 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].

• Motor

• Taste sensation

CN VII: Facial

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.

• Pt smile: compare nasolabial grooves.

• Pt show teeth, puff out cheeks.

• Taste sensation in the anterior 2/3 of the tongue.

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.

CN XII: Hypoglossal

• Inspect tongue in mouth for wasting, fasciculations.

• Protrude tongue: unilateral deviates to affected side.

Motor system

don’t forget to compare both limbs

• Inspection

• Palpation ( muscle bulk + tenderness )

• Muscle tone

• Muscle power

• Reflexes

Motor system

1. Upper limbs (compare)

• Inspect for muscle wasting ( proximal & Distal ) – scars – deformity – fasciculation – skin pigmentation.

• Drift test

• Feel the muscle bulk ( proximally & Distally ) – muscle tenderness.

• Tone ( normo – hypo – hypertonia )

by passive movement of wrist and elbow joints.

• Power ( 0 – 5 )

by active movement at the shoulder , elbow , wrists and fingers.

• Reflexes ( 0 - ++++ )

Biceps ( C5,C6 ) – Triceps ( C7,C8 ) – Brachioradialis ( C5,C6 )

• Coordination

Finger to nose test

Finger to finger test

Dysdiadochokinesis

Rebound test

2. Lower limbs

• Inspect the gait of the patient

• Expose both thighs and legs.

• Inspect for muscle wasting – scars – deformity – posture -fasciculation – skin pigmentation .

• Feel the muscle bulk and muscles for tenderness.

• Tone ( normo – hypo – hypertonia )

by passive movement of the knee and ankle joints

• Clonus more than 3

ankle and knee clonus

• Power ( 0 – 5 )

by active movement at the hip , knee , ankle , and tarsal joints

• 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

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

Back

• Inspect for deformity – scars – neurofibromas .

• Palpate for tenderness over the vertebral bodies

• Do the straight leg raising test

Auscultation

• Auscultate over the carotid arteries looking for bruits.