Motor weakness clinical approach updated 2013

1. MOTOR PARALYSIS: CLINICAL
APPROACH
Dr PS Deb MD, DM
Director Neurology
GNRC Hospitals Guwahati
Assam, India

2. ORGANIZATION OF MOTOR NERVOUS
SYSTEM

3. 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

4. MOTOR CORTEX AFFERENT
1. Adjacent cortex
1. 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).

5. CONVERGENCE OF MOTOR CONTROL ON THE
ANTERIOR MOTOR NEURON

6. EXTRAPYRAMIDAL SYSTEM

7. 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

8. CONTROL OF VOLUNTARY MOVEMENT
Idea
Association
cortex
Premotor +
Motor cortex
Basal
Ganglia
Lateral
cerebellum
Movement
Intermediate
Cerebellum
ExecutionPlanning

9. 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

10. Dominant
supramarginal
gyrus
Premotor
cortex
Motor
cortex
Arcuate fiber
Premotor
cortex
Corpus callosum
Motor
cortex
1
2
3
APRAXIA LESIONS
1. Bilateral Apraxia ideomotor
2. Left apraxia (right hemiplegia)
3. Left Apraxia sympathetic

11. 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 parietal
4. Buccofacial – Broca’s
5. Gait – Parasagiatal premotor
6. Limb kinetic – movement grossly resemble
intended gesture but is awkward (left premotor)

12. PYRAMIDAL LESION: UMN - CLINICAL
1. Weakness
1. Distribution: Brodbant’s law
2. Recovery pattern
3. Residual weakness
2. Synkinetic movement: Mirror movement
3. Tone changes:
1. Distribution
2. Character
4. Reflex:
1. Deep
2. Superficial
5. Other: Electrical stimulation

13. MOTOR CORTEX AND CORONA RADIATA
Cortex (Area 4)
 Contralateral
Hemiplegia
 Motor seizures
 Aphasia (44)
 Associated:
 Apraxia
 Agnosia
 Cortical anesthesia
 Hemianopia

14. MOTOR CORTEX AND CORONA RADIATA
Corona Radiata
 Contralateral
hemiplegia or
monoplegia
 No apraxia, agnosia,
aphasia and seizure,

15. INTERNAL CAPSULE
Contralateral Dense
Hemiplegia,
Genu: Face & Upper
limb,
Posterior Limb: Lower
Limb

16. 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

17. MID - BRAIN
 Webers Syndrome:
Contralateral
Hemiplegia , Ipsi lateral
3rd Nerve Palsy
 Benedict's Syndrome:
Contralateral
Hemiplegia , Ipsilateral
Rubral Tremor, ipsi
Lateral 3rd Nerve Palsy

18. 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

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

20. SPINAL CORD: EXTRINSIC
 Radicular involvement
 Asymetric, progression in
inverted U pattern
 Ipsi Lateral Hemiplegia,
 contralateral spinothalamic
lesion
 Ipsilateral posterior column
sensory loss

21. SPINAL CORD: INTRINSIC
 Dissociated anesthesia
 Jacket Anesthesia
 Long tract sign
 Sacral sparing
 Ant. Horn cell involvement
 Symmetrical/ Asymmetrical
 Bladder involvement

22. SPINAL CORD: BROWN SEQUARD SYNDROME
 Ipsilateral Hemiplegia,
 Contralateral
Spinothalamic lesion
 Ipsilateral posterior
column sensory loss

23. CAUSES OF HEMIPLEGIA
 Vascular
 Traumatic
 Neoplastic
 Infection
 Demyelination

24. TYPES OF HEMIPLEGIA
 Ataxic hemiparesis: Lacular infarct
 Crossed hemiparesis: Brain stem
 Alternating hemiplegia: Migraine

25. 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

26. 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

27. 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 Noncompressive
1. Motor Neuron Disease
2. Syringomyelia
3. Freidric Ataxia
4. Familial spastic paraplegia
5. Multiple Sclerosis
6. Subacute Myelooptic
Neuritis
7. Subacute Combined
Degeneration
8. Pellagra
9. Tropical spastic paraplegia
10. Larthyrism

28. 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

29. COMPRESSIVE MYELOPATHY
 Intradural
 Meningioma
 Neurofibroma
 Intramedullary
 Glioma
 Ependymoma
 AVM
 Hemangioblastoma
 Developmental Traction
 Diastomatomyelia
 Tethered Cord

30. 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

31. 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

32. MYELORADICULITIS
 Infection
 Tubercular (Arachnoiditis, Pott’s spine)
 Pyogenic
 Syphilitic
 Spine
 CV junction anomaly
 Narrow canal
 Toxic

33. 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

34. 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

35. 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

36. LMN SYNDROMES: BIBRACHIAL WEAKNESS
 Ant. Horn cell
 ALS
 Polio
 Syringomyelia
 Nerve
 AIDP
 Porphyria
 Plexus
 Brachial neuritis (rare)

37. 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

38. LIMB GIRDLE SYNDROME
 Peripheral nerve
 Diabetic proximal
 GBS
 Infectious
mononeucleosis
 Dyphtheria
 Porphyria
 Carsinomatous
 Oraganophosphorus
(TOCP)
 Neuromuscular
junction
 Myasthenic syndrome
 Ant. Horn cell
 MND
 SMA

39. 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

40. 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

41. FOCAL WEAKNESS
 Muscle
 Congenital restricted myopathy
 Peripheral nerve
 Root / plexus
 Ant horn cell
 Cord
 Cortex

42. WAISTING
 Congenital
 Lower motor neuron
 Disuse
 UMN
 Bone/ joint disease
 Systemic disease

43. 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

44. LOCALIZED MUSCLE MASS
 Rupture muscle
 Muscle hemorrhage
 Muscle tumor
 Myositis ossificans
 Granuloma
 Abscess
 Fibrositis

45. QUALITATIVE CHANGES IN MUSCLE
CONTRACTION
 Myasthenic state
 Inverse myasthenia
 Contraction myodema
 Myotonia
 Paradoxical myotonia
 Tetanus
 Contracture true/ pseudo
 Ankylosis
 Vlkman’s ischemic contraction

46. CONTINUOUS MUSCLE FIBER ACTIVITY
 Isaac Martine syndrome
 Stiffman syndrome
 Toxin
 Strychnine
 Black widow spider bite
 Tetanus

47. FASCICULATION
 Benign
 Ant horn cell disease
 Root compression
 Systemic
 Anticholene estaterase
 Thyrotoxicosis
 Electrolyte imbalance
 Alkalosis

48. MYOKIMIA
 Benign (leg, eyelid)
 Isaac martin syndrome
 Hyperthyroidism
 Uremia
 Tetany
 Facial
 MS
 Brain stem tumor
 Extramedulary post fossa tumor

49. CRAMP
 Exersion
 Dehydration and salt deplition
 Pregnancy
 Hypothyroidism
 Denervation:
 MND
 Neuropathy
 Toxic
 Diuretic
 Clofibrate
 Ant choline estarase
 Tetany
 Continuous muscle fiber activity

50. THANKS