Previous lumbar puncture

Clinical Syndromes

2.1 Previous lumbar puncture

Lesion localization Pattern of hemiplegia

Upper brainstem Weakness or paralysis of the contralateral leg, arm, and face

+ Ipsilateral oculomotor nerve palsy Midbrain: Weber syndrome

+ Ipsilateral abducens and facial palsy Lower pons: Millard-Gubler syndrome

Medulla Weakness of the contralateral leg and arm with

ipsilateral pharyngeal or laryngeal weakness Lower medulla Weakness of the contralateral or ipsilateral arm and

leg, with sparing of the face and tongue Lateral column of the cervical spinal cord Ipsilateral hemiplegia

Intracranial hypotension

1 Technical error (artifactually low intracranial pressure)

◆ Due to incomplete penetration of the subarachnoid space by the needle 2 CSF fi stulae

◆ It is the diagnosis of exclusion requiring the exclusion of the site of CSF leak.

◆ In some case reports, the sites of CSF leak were later identifi ed with more ad-vanced diagnostic technology.

4 Spinal subarachnoid block

◆ Causes include tumor, disc, or arachnoiditis 5 Severe dehydration

◆ Seen in infants, manifest by sunken fontanelle.

Kyphoscoliosis in neurological disorders

The following neurological disorders can have prominent kyphoscoliosis:

1 Neurofi bromatosis

◆ The typical clinical picture includes multiple circumscribed areas of increased skin pigmentation, accompanied by dermal and neural tumors of various types.

◆ Scoliosis is usually seen, which can be associated with other bony abnormali-ties, including bone cysts, pathological fractures, and bone hypertrophy.

2 Friedreich ataxia

◆ Although gait ataxia is usually the presenting symptom, pes cavus and kypho-scoliosis can precede other neurological symptoms.

3 Poliomyelitis

◆ Asymmetrical atrophic, arefl exic paralysis of muscles of the trunk and limbs represents a likely etiology of kyphoscoliosis associated with polio.

4 Extrapyramidal syndromes

◆ Kyphosis can be seen in Parkinson disease, sometimes called camptocormia.

◆ Scoliosis can be seen in truncal dystonia.

5 Syringomyelia – kyphoscoliosis is usually mild 6 Others

◆ Cerebral palsy

◆ Marfan syndrome

◆ Spina bifi da

◆ Tethered cord

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The most common deformities of the chest and spine are scoliosis, kyphosis, or a combination of the two.

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Kyphosis results in anterior concavity of the thoracic spine and thereby leads to shortening of the chest.

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Scoliosis is the lateral curvature of the spine with convexity to one side. Scoliosis can be functional or structural. Functional scoliosis is a compensatory posture to a number of conditions; for example, shortening of one leg, sciatica, or painful arthritis. Functional scoliosis usually

disappears on bending, but structural scoliosis caused by defi ciency, absence, or disease of the vertebrae remains unaltered when bending.

Lhermitte sign

Seen in:

1 Multiple sclerosis

2 Subacute combined degeneration of the spinal cord 3 High cervical cord compression from cervical spondylosis 4 Cerebellar ectopia

5 Early stage of radiation myelopathy

Monoplegia

1 Monoplegia without muscular atrophy

◆ Localizes to a lesion of the cerebral cortex.

■ Thrombotic or embolic vascular lesions are the most frequent cause.

◆ Subcortical lesions are unlikely to cause monoplegia.

◆ Often associated with other upper motor neuron fi ndings including spasticity, increased refl exes, Babinski sign.

2 Monoplegia with muscular atrophy

◆ More frequent than monoplegia without muscular atrophy.

◆ Can be caused by:

■ Disuse atrophy, in which refl exes are retained and nerve conduction study is normal or denervation of muscles in which there are visible fasciculations and reduced refl exes.

◆ Complete atrophic brachial monoplegia is uncommon and only parts of a limb are usually affected. Other common causes include:

■ Brachial plexus trauma in infants

■ Poliomyelitis in a child

■ Syringomyelia

■ Amyotrophic lateral sclerosis in adults

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Forward fl exion of the neck results in a burst of electric-shock-like paresthesias shooting into all four limbs, or down the center of the back.

Sometimes, this may occur only in lower limbs or even on one side only.

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Monoplegia refers to weakness or paralysis of all the muscles of one leg or arm. However, examination of patients who complain of weakness of one limb often discloses an asymptomatic weakness of another, and the condition is actually hemiparesis, in which the etiology can be different from monoplegia.

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Monoplegia can be caused by upper and lower motor neuron lesions.

Evidence of muscular atrophy is helpful in further localizing the lesion.

Muscular wasting of the small hand muscles

Causes of BILATERAL wasting of the small muscles of the hands:

1 Age-related

2 Associated with rheumatoid arthritis 3 Cervical causes:

◆ Cervical spondylosis

◆ Syringomyelia

◆ Bilateral cervical ribs 4 Motor neuron disease 5 Peripheral nerve causes:

◆ Combined bilateral medial and ulnar nerve lesions or bilateral ulnar nerve lesions

◆ Chronic infl ammatory demyelinating polyneuropathy (CIDP)

◆ Charcot-Marie-Tooth disease

Causes of UNILATERAL wasting of the small muscles of the hand:

1 Ulnar neuropathy

◆ Focal compression

◆ Overuse

◆ Associated with rheumatoid arthritis 2 C8-T1 nerve root compression 3 Brachial plexus trauma, infi ltration 4 Pancoast tumor

5 Combined medial and ulnar nerve lesions

Neck stiffness

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Intrinsic hand muscles (small muscles of the hand) include the thenar and hypothenar eminences and dorsal interrossei.

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The ulnar nerve innervates the fl exor pollicis brevis (thenar eminence), hypothenar eminence, and dorsal interossei.

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The median nerve innervates the remainder of the thenar muscles.

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Etiology is different between bilateral and unilateral wasting of the small muscles of the hand.

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Neck stiffness is not an uncommon fi nding on examination, especially in the emergency room setting.

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Although neck stiffness may raise the possibility of meningeal irritation, many elderly patients, children, and chronically ill patients may have a stiff neck that does not represent central nervous system involvement.

1 Neurological causes

1.1 Meningeal irritation – usually indicates a neurological emergency. There-fore, the following conditions should be excluded:

■ Infection, e.g. bacterial meningitis

■ Neoplasia, e.g. leptomeningeal carcinomatosis

■ Subarachnoid hemorrhage (triad includes sudden onset of headache, de-pressed consciousness, and stiff neck/meningismus)

1.2 Axial rigidity/stiffness

■ Extrapyramidal syndromes, including Parkinson disease, Parkinson-plus syndrome (e.g. progressive supranuclear palsy)

■ Dystonia, e.g. cervical dystonia, generalized dystonia

■ Stiff-man or stiff-person syndrome

1.3 Secondary paravertebral muscle spasm due to cervical spine disease or ra-diculopathy.

2 Non-neurological causes

2.1 Cervical spine traumatic injury – locked facet, fracture/dislocation, severe muscle spasm. Of course, the possibility for this to result in signifi cant neu-rological injury must not be overlooked.

2.2 Degenerative cervical spine disease 2.3 Muscle sprain

2.4 Part of the spectrum seen in catatonia

Palatal myoclonus

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In the presence of neck stiffness along with other fi ndings of meningeal irritation (such as Kernig or Brudzinski signs), and in the absence of signs of increased intracranial pressure, lumbar puncture should be performed to defi ne the etiology. If acute bacterial meningitis is suspected, antibiotics must be initiated before cultures become positive.

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In the presence of neck stiffness in patients with depressed consciousness, the possibility of a mass lesion with rupture or herniation needs to be excluded before lumbar puncture is performed.

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‘Palatal tremor’ is perhaps a better term.

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A rhythmic contraction (60–180/min) affecting the palatal and pharyngeal structures.

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Often associated with synchronous movements of the ocular muscles, diaphragm, head, and neck.

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Persists in sleep.

Differential localizations:

1 Gullain-Mollaret triangle lesion

◆ Pathway between the red nucleus, inferior olivary nucleus, and dentate nucleus.

◆ Case reports with vascular, traumatic, neoplastic, and demyelinating lesions 2 Rare localizations

◆ Cortical palatal myoclonus

◆ Epileptic palatal myoclonus (secondary to epilepsia partialis continua) 3 Psychogenic palatal tremor (recently reported)

Paraplegia

1 Spinal cord lesion

◆ Paralysis and weakness affect all muscles below a given level.

◆ If the lesions are bilateral, bowel and bladder function are often affected.

◆ The most common cause of ACUTE paraplegia is:

■ Spinal cord trauma, associated with fracture dislocation of the spine.

◆ Less common causes include:

■ Hematomyelia from AVM

■ Infarctions of the cord

■ Myelitis.

◆ In adults, the most common causes of CHRONIC OR SUBACUTE paraplegia are:

■ Multiple sclerosis

■ Tumors.

◆ In children, congenital cerebral disease from periventricular leukomalacia ac-counts for a majority of cases of infantile diplegia.

2 Peripheral nerve lesions

◆ Motor involvement tends to be in distal groups rather than proximal ones.

◆ Sensory loss, if present, follows a peripheral nerve pattern rather than a der-matomal pattern.

◆ Sphincter functions are usually preserved and sensory loss is usually in the distal segments.

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Paraplegia refers to paralysis of both lower extremities.

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If the onset is acute, it may be diffi cult to differentiate a spinal cause from a neuropathic process. This is because acute spinal shock results in early abolition of refl exes and fl accidity, and increased tone and hyperrefl exia develop only with time.

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All spinal causes of paraplegia also apply to quadriplegia, with the lesion being in the cervical rather than the thoracic or lumbar segments of the spinal cord.

3 Cauda equina lesions

4 Bilateral medial frontal lobe lesions or parasagittal lesions (e.g. falcine meningi-oma)

5 Pseudotumor cerebri (benign intracranial hypertension)

Pes cavus

1 Isolated fi nding with no association with neurological disorders

◆ Most common.

2 Friedreich ataxia

◆ Most common inherited autosomal recessive ataxia.

◆ Predominant features include ataxia, clumsiness, dysarthria, peripheral neu-ropathy and dorsal column dysfunction.

3 Charcot-Marie-Tooth disease (CMT) or hereditary motor sensory neuropathy (HMSN)

◆ Most common form of inherited peripheral neuropathy.

◆ The hallmarks of this syndrome are genetic transmission, symmetry of affec-tion, slow progression, degeneration of functionally related systems of fi bers, and axonal myelin fi ber loss.

4 Syringomyelia 5 Spina bifi da

Pyramidal versus extrapyramidal syndromes: spasticity vs. rigidity

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The intrinsic muscles of the sole of the foot run along the longitudinal arch of the foot. The short muscles of the foot are particularly responsible for the management of the arch and any dysfunction of these muscles may result in pes cavus.

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In addition, increased height of the longitudinal arch can be associated with dorsal contracture of the metatarsophalangeal joints resulting in pes cavus.

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In most cases, pes cavus is not associated with any neurological conditions.

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The terms pyramidal, corticospinal, and upper motor neuron are often used interchangeably. The pyramidal tract, strictly speaking, designates only those fi bers that course longitudinally in the pyramid of the medulla.

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The term ‘extrapyramidal’ refers to all the motor pathways except pyramidal ones. The term is imprecise and includes the basal ganglia and the cerebellum, which function very differently in the control of movement and posture.

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Different clinical features and signs distinguish between pyramidal and extrapyramidal syndromes. They are often helpful in disease localization and when considering pathological process.

Features Pyramidal Extrapyramidal Characteristic of the muscle

tone alteration

Spasticity (clasp-knife effect) Plastic (equal throughout passive movement-rigidity), or intermittent (cogwheel rigidity) Distribution of hypertonus Flexors of arms

Extensors of legs

Generalized, but predominates in fl exors of limbs and of trunk Shortening and lengthening

reaction

Present Absent

Involuntary movements Absent Can be present, including

tremor, chorea, myoclonus, etc.

Tendon refl exes Signifi cantly increased Normal or slightly increased

Clonus Present Absent

Babinski sign Present Absent

Paralysis of voluntary movements

Present Absent or slight

Ref: Modifi ed from Adams and Victor, Principles of Neurology, 7th edition.

Recurrent falls: neurological causes

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These clinical signs may be seen in isolation or combination.

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Rigidity is an extrapyramidal sign.

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Spasticity is a pyramidal sign.

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Etiologies for both phenomena are vast and include vascular, hereditary, demyelinating, and neurodegenerative conditions.

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Although falling is not a common cause for neurological referral, there are special circumstances that affect postural control mechanisms for which neurological evaluation is warranted.

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Orthostatic hypotension is identifi ed as a factor in 5–10% of falls and should always be considered as a treatable non-neurological cause.

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Intoxication with medications, alcohol, or drugs should also be considered as a common non-neurological cause of recurrent falls.

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Drop attacks are defi ned as sudden lapses of postural tone and collapse without loss of consciousness. Drop attacks are rare causes of recurrent falls.

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Subdural hematoma is always a concern as a complication in patients with recurrent falls. A low threshold for imaging is appropriate in this group of patients.

1 Neurological disorders that affect the postural control 1.1 Parkinson disease

1.2 Other akinetic-rigid syndromes

■ Parkinson-plus syndromes

■ Progressive supranuclear palsy

■ Multiple system atrophy 2 Cerebellar degeneration

■ Patients with ataxia have poorly coordinated postural synergies.

■ Ataxic patients commonly present with falls.

3 Sensory defi cits

3.1 Sensory defi cits affecting proprioception

■ These patients usually have a positive Romberg test and complain of in-creasing unsteadiness in the dark.

■ Severe peripheral neuropathy can result in unsteadiness.

3.2 Vestibular dysfunction

■ Patients with bilateral vestibular defi cits are particularly unsteady in stance.

3.3 Visual impairment

4 Recurrent falls associated with dementia

◆ The pathophysiology of falls in this context is not well understood.

◆ There may be a failure of attention or integrative control of posture at a high level.

Romberg sign

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The Romberg is a test of proprioceptive function. The patient is asked to stand with the feet closely approximated, fi rst with his/her eyes open, and then closed. The position of the body as a whole and that of the feet, shoulders, and head should be noted, as should any tremors, swaying or lurching.

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Slight swaying with the eyes shut may occur in some normal individuals.

The test is ‘positive’ when the patient is able to stand with his/her feet together while his/her eyes are open, but sways or falls when they are closed.

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Any lesions along the proprioceptive pathway can result in a positive

Romberg test. The peripheral sense organs are located in the muscle, tendons, and joints. The fi rst cell body is situated in the dorsal root ganglion, going without a synapse to the ipsilateral fasiculi cuneatus and gracilis to the lower medulla where the synapse occurs. Following a decussation of the internal arcuate fi bers, the impulses ascend in the medial lemniscus to the thalamus, terminating in the parietal lobe, posterior to those that convey touch.

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In a false Romberg test, seen in conversion reaction, the patient sways from the hips instead of from the ankles. He/she may sway through a wide arc and it may seem inevitable that he/she will fall, but he/she is usually able to regain his/her balance and resume the upright position.

Conditions commonly causing a positive Romberg test:

1 Posterior column dysfunction

◆ Posterior cord compression

◆ Multiple sclerosis

◆ Subacute combined degeneration of the spinal cord

◆ Tabes dorsalis

2 Sensory polyneuropathy

◆ Idiopathic

◆ Diabetes mellitus 3 Intracranial lesions

◆ Less common.

◆ Associated features involving surrounding structures are usually present, for example, other brainstem fi ndings.

Scapular winging

Causes:

1 Isolated or combined neuropathies:

◆ Long thoracic nerve neuropathy (most common) causes serratus anterior weakness. It is usually due to acute or chronic neck trauma, and is described in workers carrying heavy, angular loads on the shoulder (hod carrier palsy).

◆ Spinal accessory nerve neuropathy causes trapezius weakness.

2 C5, 6 radiculopathy

3 Proximal brachial plexopathy

4 Myopathies: rare, usually occur as part of diffuse conditions.

5 Spinal muscular atrophy

Temperature-sensitive neurological conditions

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Scapular winging is seen in weakness of the serratus anterior, trapezius and rarely, rhomboid muscles.

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In serratus anterior weakness, the winging at rest is negligible and worsens with shoulder fl exion. These patients may have diffi culty abducting the shoulder >90 degrees. The vertebral scapular border lies close to the midline (medial translocation) and its lower border rotates medially.

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In trapezius weakness, the winging is present at rest and worsens with shoulder abduction. Findings become less prominent with abduction >90 degrees. The scapula is farther from midline (lateral translocation). The levator scapulae is prominent due to atrophy of the trapezius.

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Patients with certain neurological diagnoses will report subjective or objective changes in their neurological symptoms based on temperature.

1 Worsened by a rise in body temperature:

◆ Multiple sclerosis

◆ Myasthenia gravis

◆ Eaton-Lambert syndrome

◆ Febrile seizures

2 Worsened by a low body temperature:

◆ Paramyotonia

Upper vs. lower motor neuron distinctions

Sign or symptom Upper motor neuron Lower motor neuron Paralysis or paresis Yes, although muscles affected in

groups, not individual muscles

Yes, with individual muscles affected

Effect on residual movement

Increased degree of co-contraction of antagonistic muscles

No evidence of co-contraction of antagonistic muscles

Muscle tone Increased Decreased

Refl exes Increased Decreased or absent

Clonus May be present Absent

Babinski sign Present Absent

Fibrillations Absent May be present

Fasiculations Absent May be present

Muscle atrophy Absent (early) Present

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Upper motor neuron lesions describe pathologies of the descending motor pathway from the cortex through spinal cord, proximal to the anterior horn cells. Lower motor neuron lesions are the direct result of loss of function of anterior horn cells or their axons in anterior roots and peripheral nerves.

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Differentiation between upper and lower motor neuron lesions is an important aspect of neurological localization.

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Nerve conduction study and electromyography are useful tools in confi rming lower motor neuron lesions, further localizing the lesion, and providing clues on underlying pathophysiology. In lower motor neuron lesion, EMG is abnormal with fi brillations, fasciculations, and positive sharp waves, while the tests are usually normal in upper motor neuron lesions.

Named syndromes Alien limb syndrome

Causes:

1 Corticobasal ganglionic degeneration (CBGD)

◆ Cortical refl ex myoclonus is frequent.

2 Infarcts: the following lesions have been reported.

◆ Corpus callosum

◆ Mesial frontal lesions

◆ Combination of posterior corpus callosum and thalamic lesions 3 Others

◆ Alzheimer disease

◆ Anterior communicating artery rupture

◆ Corpus callosotomy

◆ Corpus callosal tumors

◆ Bifrontal penetrating injury

Balint syndrome

1 Etiology:

◆ Bilateral watershed infarct between the middle and posterior circulation is the most common cause.

2 Signs and symptoms:

◆ Psychic paralysis of gaze: inability to voluntarily look into the peripheral fi eld.

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Failure to recognize ownership of one’s limb when visual cues are removed;

a feeling that one body part is foreign.

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The hand is most frequently affected, but any limb or combinations may occur.

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Patients have apraxia, problems with bimanual coordination and display non-goal directed activities.

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Balint syndrome refers to a syndrome consisting of:

1 Psychic paralysis of gaze 2 Optic ataxia

3 Disturbance of visual attention, particularly in the peripheral visual fi eld.

4 Simultagnosia

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Almost invariably associated with large bilateral parietal lobe lesions.

◆ Optic ataxia: clumsiness or inability to manually respond to visual stimuli, with mislocation in space when pointing to visual targets.

◆ A disturbance of visual attention: resulting in dynamic concentric narrowing of the effective fi eld.

◆ Simultagnosia: an inability to recognize the whole picture despite the ability to perceive its parts.

◆ Inferior altitudinal fi eld defect: not part of Balint syndrome, but upper banks of occipital cortex are usually involved.

3 Treatment:

◆ According to the etiology of stroke.

Cavernous sinus syndrome

1 Tumors

◆ Most common cause.

◆ The most common neoplastic lesion in the cavernous sinus is caused by direct invasion from nasopharyngeal carcinoma. Metastatic lesions are the second most common.

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The cavernous sinus is a small but complex structure consisting of a venous plexus, carotid artery, cranial nerves, and sympathetic fi bers, surrounded by a dural fold.

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The third, fourth cranial nerves, as well as the fi rst and second divisions of the trigeminal nerve (V1 and V2), lie along the lateral wall of the cavernous sinus, whereas the sixth cranial nerve, internal carotid artery, and the third-order oculosympathetic fi bers from the superior cervical ganglion lie more medially.

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According to the anatomy described above, cavernous sinus involvement would be suggested by any combination of unilateral third-, fourth-, or sixth-nerve dysfunction, accompanied by hypesthesia of the forehead, cornea, or cheek, or by Horner syndrome. Various degrees of pain may be involved. Complete interruption of all three ocular motor nerves would result in total ophthalmoplegia, ptosis, and/or mydriasis.

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Although the classical syndrome of cavernous sinus results from aneurysm or carotico-cavernous fi stula, the most common causes of cavernous sinus lesions include tumors, trauma, and infections.

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Except for sparing of V2, lesions of the superior orbital fi ssure are clinically diffi cult to distinguish from those of cavernous sinus, and the differentials are similar. In orbital apex syndrome, patients present with third-, fourth-, and sixth-nerve palsies, V1 distribution sensory loss, oculosympathetic paresis, and visual loss due to optic nerve involvement.

2 Trauma

◆ Trauma is reported to be the most common cause of cavernous sinus syn-drome when surgical cases are included.

3 Infections or cavernous sinus thrombophlebitis

◆ Thrombophlebitis of the cavernous sinus is potentially a lethal condition, caused by bacterial or fungal invasion, complicating sinusitis in patients with poorly controlled diabetes or immunosuppression.

◆ Rhinocerebral mucormycosis is a common cause in poorly controlled diabetics.

◆ Aspergillosis arises most commonly as a result of hematogenous spread, and occasionally by direct extension of infection from the paranasal sinuses, mid-dle ear, or orbit in immunocompromised patients.

◆ Actinomycosis gains access to the cavernous sinus by direct extension from the ear, sinus, and less commonly, hematogenous spread. Most patients are immunocompetent.

4 Tolosa-Hunt syndrome

◆ Tolosa-Hunt syndrome is a recurrent painful ophthalmoplegia due to nonspe-cifi c granulomatous infl ammation in the anterior cavernous sinus, superior orbital fi ssure, or orbital apex.

◆ Rare cause of cavernous sinus syndrome.

◆ The diagnosis is based on fi ndings of painful ophthalmoplegia, accompanied by variable defi cits of cranial nerves in the cavernous sinus, excellent response to corticosteroid therapy, and exclusion of other causes.

5 Carotico-cavernous fi stula (CCF)

◆ CCF usually result from traumatic laceration of the carotid artery or from rupture of an aneurysm into the surrounding venous sac, establishing a direct communication between internal carotid artery and the venous spaces of the cavernous sinus.

◆ Pulsating exophthalmos, orbital pain, and, eventually, restriction of eye move-ments due to orbital congestion.

6 Other rare causes

◆ Aneurysm of the internal carotid artery

◆ Infl ammatory pseudotumors

Central pontine myelinolysis (CPM): causes

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Central pontine myelinolysis (CPM) is a demyelinating disease of the pons, frequently associated with demyelination of other areas of the central nervous system. The term ‘osmotic demyelination syndrome’ is used for pontine and extrapontine myelinolysis (CPM/EPM).

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The etiologies of CPM/EPM vary. However, almost all cases are related to severe illnesses, with chronic alcoholism being the most common

underlying condition. A signifi cant high percentage of CPM/EPM cases were also observed among liver transplant patients.