MOTOR PARALYSIS: CLINICAL APPROACH

Dr PS Deb MD, DM

Director Neurology

GNRC Hospitals Guwahati

Assam, India

ORGANIZATION OF MOTOR NERVOUS SYSTEM

MOTOR CORTEX

Cell types : Betz cell 35000 Origin of pyramidal tract in monkey – Russel

Demayer Frontal lobe - Area 4 31%, Area 6 29%, Parietal lobe 40% No of pyramidal fibers at medulla 10,00,000

MOTOR CORTEX AFFERENT

1. Adjacent cortex1. the somatosensory areas of the

parietal cortex,

2. theadjacent areas of the frontal cortex anterior to the motor cortex, and

3. the visual and auditory cortices.

2. Opposite cerebral hemisphere.

3. Somatosensory fibers directly from the ventrobasal complex of the thalamus.

4. Tracts from the ventrolateral and ventroanterior nuclei of the thalamus, which in turn receive signals from the cerebellum and basal ganglia

5. Fibers from the intralaminar nuclei of the thalamus (RAS).

CONVERGENCE OF MOTOR CONTROL ON THE ANTERIOR MOTOR NEURON

EXTRAPYRAMIDAL SYSTEM

SUMMARY Primary Motor Cortex:

Codes force and direction of movement Spinal motor neuron are directly under control for

precise movement. Dorsal Premotor Cortex

Movement related neuron encodes sensorimotor transformation for visual and sensory cue

Fire before movement Ventral Premotor Cortex

Encodes learned motor act fire before movement

All cortical neurons are adaptable and plastic

CONTROL OF VOLUNTARY MOVEMENT

IdeaAssociation cortex

Premotor + Motor cortex

Basal Ganglia

Lateral cerebellum

Movement

Intermediate

Cerebellum

ExecutionPlanning

APRAXIA

Loss of ability to execute learned sequence of movement on command in absence of motor, sensory, cerebellar or extrapyramidal derangement in conscious cooperative patient. (Lipmann 1900)

Loss of memory of sequence of learned act. Common disorder but missed

Usually present in acute lesion and disappear rapidly when patient improve

Usually associated with weakness and aphasia If not tested patient only use object but cannot

pantomime

Dominant supramarginal

gyrus

Premotor cortex

Motor cortex

Arcuate fiber

Premotor cortex

Corpus callosum

Motor cortex

1

2

3

APRAXIA LESIONS

1. Bilateral Apraxia ideomotor2. Left apraxia (right hemiplegia)3. Left Apraxia sympathetic

APRAXIA TYPES

1. Ideational – unable to do sequential task, can do individual task (left parietal) light a match

2. Ideomotor – unable to do even individual task (left premotor)

3. Dressing + Construction – Right parietal4. Buccofacial – Broca’s5. Gait – Parasagiatal premotor6. Limb kinetic – movement grossly resemble

intended gesture but is awkward (left premotor)

PYRAMIDAL LESION: UMN - CLINICAL

1. Weakness1. Distribution: Brodbant’s law2. Recovery pattern3. Residual weakness

2. Synkinetic movement: Mirror movement3. Tone changes:

1. Distribution2. Character

4. Reflex:1. Deep2. Superficial

5. Other: Electrical stimulation

MOTOR CORTEX AND CORONA RADIATA

Cortex (Area 4) Contralateral

Hemiplegia Motor seizures Aphasia (44) Associated:

Apraxia Agnosia Cortical

anesthesia Hemianopia

MOTOR CORTEX AND CORONA RADIATA

Corona Radiata Contralateral

hemiplegia or monoplegia

No apraxia, agnosia, aphasia and seizure,

INTERNAL CAPSULE

Contralateral Dense

Hemiplegia,

Genu: Face & Upper

limb,

Posterior Limb:

Lower Limb

BRAIN STEM

Extrinsic lesion Cranial nerve first Hearing loss

common Long tract sign late

Intrinsic lesion Long tract early

Corticospinal – ant lateral

Spinothalamic – Post lateral

Post column – Medial Cerebellar – Medial

Horner’s , INO, gaze palsy

Crossed Hemiplegia Ataxic Hemiparesis Cranial nerves

MID - BRAIN

Webers Syndrome: Contralateral Hemiplegia , Ipsi lateral 3rd Nerve Palsy

Benedict's Syndrome: Contralateral Hemiplegia , Ipsilateral Rubral Tremor, ipsi Lateral 3rd Nerve Palsy

PONS Millard Gubler

Syndrome Contralateral, Hemiplegia, 6th & 7th Nerve Palsy

Foville Syndrome : Contralateral hemiplegia 6th & 7th Nerve Palsy , Ipsi Lateral Gaze Palsy

Ataxic hemiparesis Clumsy hand

syndrome

MEDULLA

Median Medullary Syndrome : Contralateral Hemiplegia, Posterior Column Ipsilateral 12th Nerve Palsy

SPINAL CORD: EXTRINSIC

Radicular involvement

Asymetric, progression in

inverted U pattern

Ipsi Lateral Hemiplegia,

contralateral spinothalamic

lesion

Ipsilateral posterior column

sensory loss

SPINAL CORD: INTRINSIC

Dissociated anesthesia

Jacket Anesthesia

Long tract sign

Sacral sparing

Ant. Horn cell involvement

Symmetrical/ Asymmetrical

Bladder involvement

SPINAL CORD: BROWN SEQUARD SYNDROME

Ipsilateral

Hemiplegia,

Contralateral

Spinothalamic lesion

Ipsilateral posterior

column sensory loss

CAUSES OF HEMIPLEGIA

Vascular Traumatic Neoplastic Infection Demyelination

TYPES OF HEMIPLEGIA

Ataxic hemiparesis: Lacular infarct Crossed hemiparesis: Brain stem Alternating hemiplegia: Migraine

MONOPLEGA

Usually part of asymmetric hemiplegia, paraplegia Partial weakness Ataxia Sensory loss Pain

UMN: Vascular, Demyelination, tumor, abscess, granuloma, Cortical Subcortical Internal capsule Brain Stem Spinal Cord: Demyelination, tumor

MONOPLEGIA: LMN

Ant horn cell: Poliomyelitis ALS Syringomyelia (upper limb)

Ant. Root and Plexus Brachial and lumbosacral with sensory loss

Nerve Focal paralysis in the distribution of nerve With sensory loss

PARAPLEGIA Cerebral

Parasagital Meningioma Tuberculoma

Acute Trauma Vascular

Infarction Hematoma

Intra-medulary Extra- medulary

Infection Polio Epidural Abscess

Demyelination Transverse myelitis Gullain Barre’ Syndrome

Chronic Spastic

Noncompressive1. Motor Neuron Disease2. Syringomyelia3. Freidric Ataxia4. Familial spastic

paraplegia5. Multiple Sclerosis6. Subacute Myelooptic

Neuritis7. Subacute Combined

Degeneration8. Pellagra9. Tropical spastic

paraplegia10. Larthyrism

COMPRESSIVE MYELOPATHIES

Extradural Bone

Neoplastic Secondries Osteosarcoma

Infection Tuberculosis Pyogenic

Disc Prolapse Stenosis Anomalies

Meningies Inflammation

Arachnoiditis Tubercular Syphilitic Toxic

Abscess AIDS

Tumor Dermoid Epidermoid Lipoma

COMPRESSIVE MYELOPATHY

IntraduralMeningiomaNeurofibroma

IntramedullaryGliomaEpendymomaAVMHemangioblastoma

Developmental TractionDiastomatomyeliaTethered Cord

CLINICAL SYNDROMES

MON: Myelooptic Neuritis MR : Myeloradiculopathy MN : Myeloneuropathy SA : Spastic ataxic DS : Dissociated Sensory SAM : Spastic, Amyotrophic PS : Pure Spastic TM : Transverse Myelopathy PP : Painful paraplegia Qudriplegia, Parplegia, Cruisiate hemiplegia

MYELO-OPTIC NEURITIS

Demyelinating Multiple sclerosis Devic’s disease

Nutritional Subacute combined degeneration Pellagra Tropical spastic paraplegia

Toxic Lathyrism SMON

Hereditary Familial spastic paraplegia with optic atrophy

MYELORADICULITIS

Infection Tubercular (Arachnoiditis, Pott’s spine) Pyogenic Syphilitic

Spine CV junction anomaly Narrow canal

Toxic

PARPLEGIAS

Flaccid Parplegias Ant. Horn Cell Dis. Cauda equina Poly rediculitis Polyneuropathis Myasthenia Muscular Dystrophy

Dissociative Paralysis Atypical

presentation Hoover’s Sign Babinski’s combined

leg flexion test

LOWER MOTOR NEURON WEAKNESS Anatomy

Motor neuron Roots Plexus Nerve Muscle

Physology Movement

Agonist: Prime movers Antagonist Synergist: Prevent other

movement of primemovers Fixators

Speed Fast: Phasic, ballistic Slow: Tonic, ramp movement

Clinical pattern Weakness: Pattern,

distribution Tone Wasting: 80% in

two months Fasciculation Fibrillation Loss of reflex No response to

electrical stimulation

LOCALIZATION OF LMN LESIONS

Ant. Horn Cells Atrophy Fasciculation Proximal, distal,

asymmetrical All muscles of the

same segment not affected

Patchy involvement of muscles

Roots , Plexus Proximal Asymmetrical All muscles of the same root

affected Atrophy Fasciculation Areflexia

Nerves Distal Sensory loss Arflexia Anatomical distribution

Muscles Proximal, distal rare Symmetrical Retained reflexes

LMN SYNDROMES: BIBRACHIAL WEAKNESS

Ant. Horn cell ALS Polio Syringomyelia

Nerve AIDP Porphyria

Plexus Brachial neuritis (rare)

LIMB GIRDLE SYNDROME: MUSCLES Dystrophies

Duchene Becker Limb Girdle

Congenital Central core Nemalin rod Myo-tubular Fiber type disproportion

Inflammatory Poliomyelitis Dermatomyositis Collagen Vascular Sarcoidosis

Endocrine Hyperthyroidism Hyperparathyroidism Cushing’s Syndrome Acromegaly Primary

Aldoesteronism Metabolic/toxic

Acid Maltase deficiency

Periodic paralysis Carnitine deficiency Alcohol myopathy

LIMB GIRDLE SYNDROME

Peripheral nerve Diabetic proximal GBS Infectious

mononeucleosis Dyphtheria Porphyria Carsinomatous Oraganophosphorus

(TOCP)

Neuromuscular junction Myasthenic

syndrome Ant. Horn cell

MND SMA

DISTAL WEAKNESS

Muscles Myotonic dystrophy Scapuloparoneal Distal myopathy

Nerve Heriditary

Paroneal muscular atrophy

Hypertrophic polyneuropathy

Refsum disease

Toxic/Metabolic Lead Dyphtheria Porphyria

Demyelinating CIDP

Root/plexus/nerve Thoracic outlet Cauda/ conus

Ant horn cell SMA distal MND Syrings Polio

ACUTE/SUBACUTE TOTAL PARALYSIS

Muscle Ac. Polio Periodic paralysis Rhabdomyositis Paroxysmal

myoglobinuria Neuromuscular Jun.

Myasthenic syndrome Botulism Organophosphorus Succinyl choline

deficiency

Peripheral nerve AIDP Diphtheria Tick paralysis Shell fish poisoning Hypermagnicemia Porphyria

Ant. Horn cell Polio Jap B

FOCAL WEAKNESS

Muscle Congenital restricted myopathy

Peripheral nerve Root / plexus Ant horn cell Cord Cortex

WAISTING

Congenital Lower motor neuron Disuse

UMN Bone/ joint disease Systemic disease

HYPERTROPHY OF MUSCLE

Duchene’ dystrophy Becker’ dystrophy Limb girdle dystrophy Myotonia congenita Hypothyroidism De Lange’s Syndrome (hypertrophy, athetosis,

MR) Cysticercosis Malignant hyperpyrexia Hypertrophia musculorum vera Ch. Radiculopathy Kocher Derie Samelainge syndrome:

Hypothyroidsm and hypertrophied muscle

LOCALIZED MUSCLE MASS

Rupture muscle Muscle hemorrhage Muscle tumor Myositis ossificans Granuloma Abscess Fibrositis

QUALITATIVE CHANGES IN MUSCLE CONTRACTION

Myasthenic state Inverse myasthenia Contraction myodema Myotonia Paradoxical myotonia Tetanus Contracture true/ pseudo Ankylosis Vlkman’s ischemic contraction

CONTINUOUS MUSCLE FIBER ACTIVITY

Isaac Martine syndrome Stiffman syndrome Toxin

Strychnine Black widow spider bite Tetanus

FASCICULATION

Benign Ant horn cell disease Root compression Systemic

Anticholene estaterase Thyrotoxicosis Electrolyte imbalance Alkalosis

MYOKIMIA

Benign (leg, eyelid) Isaac martin syndrome Hyperthyroidism Uremia Tetany Facial

MS Brain stem tumor Extramedulary post fossa tumor

CRAMP

Exersion Dehydration and salt deplition Pregnancy Hypothyroidism Denervation:

MND Neuropathy

Toxic Diuretic Clofibrate Ant choline estarase

Tetany Continuous muscle fiber activity

THANKS