Neurological examination Flashcards
Common symptoms of neurological disease
Headaches
Dizzyness
Loss of consciousness (blackouts)
Vertigo
Loss of hearing
Speech disorder (dysphonia, dysarthria)
Sensory (pain, numbness)
Visual disorders (field loss, pupillary reflexes)
Motor disorders (paralysis tremor, co-ordination, twitching, gait)
High functional disorders (memory, psychiatric)
Name two abnormalities of language and speech
Dysphasia: impairment of language function
Dysarthria: impaired articulation due to defective movement of the lips, tongue or palate. Can be due to cerebellar or motor dysfunction
Dysphonia: impairment of sound production due to vocal cord lesions
Main tests of sensation
Touch - cotton ball
Pain - pinprick
Vibration - tuning fork
Proprioception - joint movements
Temperature (if senses unexpectedly normal)
Two point discrimination (calipers)
Name the deep tendon reflexes performed when assessing the PNS
Biceps – C5/6.
Supinator (brachioradialis) – C5/6.
Triceps – C7/8.
Patellar – L3/4.
Ankle (achilles) – S1/2.
Muscle wasting
Associated with physical inactivity and myopathies. Normally symmetrical.
Lesions in lower motor neurons cause asymmetrical wasting
Fasciculation
Visible muscle twitching at rest. Suggests lesions of lower motor neurons
What are the three types of tremor?
Tremors are caused by alternate contraction and relaxation of certain muscle groups.
Action: exaggeration of normal physiological tremor in smooth muscle movements. Common in anxiety, hyperthyroidism and alcohol withdrawal.
Rest: tremor maximal at rest, absent during movement. Typically occurs in Parkinsons
Intention: maximal during movement, absent at rest. Characteristic of cerebellar disorders
Babinski sign
Plantar reflex tested by drawing a sharp point along the lateral border from the heel towards the toes. The normal response is flexion (curling) of the toes. In a positive Babinski sign there is extension and fanning of the toes.
Due to a lesion of the upper motor neuron.
Cerebellar ataxia
Incoordination that is unaffected by visual feedback. Causes an overshoot of the finger-nose test. Associated with an intention tremor
Sensory ataxia
Incoordination due to poor proprioception. More pronounced if patient has eyes closed.
How may patients with abnormalities of the parietal lobe or thalamic projections to the parietal lobe present?
Parietal lobe is the main sensory area of the cortex. Patient may have:
sensory inattention: inability to feel a tactile stimulus
abnormal touch localisation
graphesthesia: inability to recognise writing on the skin
sterognosis: inability to perceive and recognise an object by handling it.
abnormal 2-point discrimination
How would you test for sensory inattention?
Ask patient to close their eyes and touch right, left then both shoulders. Ability to feel touch on both sides separately but not when touched simultaneously denotes inattention
Causes of mononeuritis multiplex
Diabetes
Alcohol
Vasculitis
Syphilis - multiple named nerves affected
Radicular lesions
Deficit limited to a single nerve root or a number of roots close together
Causes of peripheral neuropathy
Diabetes, alcohol, vitamin B12 deficiency, drugs
Distal sensory loss in the hands and feet.
Features of cerebellar lesions
Dysdiadochokinesia/dysmetria
Ataxia
Nystagmus
Intention tremor
Slurred speech/scanning dysarthria
Hypotonia
Sydenham’s chorea
Complication of streoptococcal infection. Caused by streptococcal antibody which damages striatal inhibitory neurons. Associated with rheumatic fever.
What other neurological tests can be done following examination
Lab tests - blood tests, biospy Lumbar puncture EEG Nerve conduction tests EMG
How would you test the integrity of peripheral nerves?
Nerve conduction test. Used to detect the presence or absence of responses and test the nerve conduction velocity in sensory and motor neurones. Electrodes are placed on two points along the course of the nerve. The nerve is stimulated electrically and the response is recorded. Repetitive stimulation is used to test the NMJ.
How can you distinguish between different types of damage using nerve conduction tests
Compression leads to focal slowing of activity. Neuropathy results in general slowing of conduction Decrease in amplitude of the wave means there is a problem with transmitter release e.g. myasthenia gravis.
Use of electromyography
Used to measure control of muscle. Measures action potentials in motor units. Can be used to distinguish between neuopathic and myopathic disorders. Fibrillation responses indicate muscle hyperexcitability following denervation. Fasciculation responses indicate spontanous activation of individual motor units.
Electroencephalogram
EEG is a recording of electrical potential changes in the cerebral cortex obtained by using electrodes on the scalp.
Normal patterns are seen in wakefulness, abnormal discharges recorded in epilepsy, encephalitis, dementia.
Overview of nervous system examination
Inspection: posture, gait, muscle wasting, tremor, abnormal movements, vision, hearing, speech, syndromes.
Palpation: assessment of sensory and motor function.
Auscultation: bruits, tinnitus (objective).
How is muscle tone assessed?
Observe limb posture
Assess passive movements at the joints (shoulder, elbow, wrist, hip, knee, ankle)
Compare sides
Muscle rigidity
Increase in muscle tone which causes resistance to passive movements.
Lead-pipe rigidity: resistance to movement throughout the entire range of movement
Cog-wheel rigidity: periodic resistance to movement in a limb, results in jerks
Clasp-knife rigidity: after an initial resistance to movement, there is a sudden reduction in tone and the limb moves freely throughout the rest of the range of movement.
Tests to assess motor co-ordination
alternating movements (dysdiadokinesia)
finger-nose test (tremor, past pointing)
Heel-toe walking
Heel-knee-shin test
Signs of raised ICP
seizures
bradycardia and hypertension
papilloedema
