Dr. Tahir Bashir Assistant Professor Medical Unit-4
Aug 18, 2015
Upper Motor neuron lesionMotor cortexDescending motor axons
Causes: Cerebrovascular accident(Infarct/bleed) Tumour Demyelination
Lower motor neuron lesionAnterior horn cellsAnterior horn cells Poliomyelitis, Motor neuron disease
Peripheral nervePeripheral nerve Peripheral neuropathy
Neuromuscular junctionNeuromuscular junction Myasthenia gravis
MusclesMuscles Muscular dystrophies
HemiparesisParaparesisQuadriparesisMonoparesisDistal weaknessProximal weaknessWeakness in restricted area
HemiparesisHemiparesis• Cortical
– Language– Sensory disturbance– Apraxia– Seizures– Visuospatial integration disorder– Homonymous field defects
• Cranial nerve– Crossed– Uncrossed
• High cervical spine– No cranial nerves involved – Face is not involved– Sensory disturbance– Ipsilateral proprioception– Control pain and temperature– Brown sequard
CrossedFacial involved on same side or any other
cranial nerve involved (midbrain, Pons, Medulla)
Hemiparesis of opposite side.
Etiology of HemiparesisAcute
Infarction Hemorrhage TraumaMultiple sclerosisBrain abscessSarcoidosis
InvestigationsCT BrainMRI BrainMRI High Cervical Spine
ParaparesisParaparesis• Brain Parasagittal Lesion / hydrocephalus• Spinal cord at or below upper thoracic• Anterior Horn Cells• Cauda Equina Syndrome (Hip flexion / sensation over
anterolateralthigh spared)
• Peripheral neuropathy GB Syndrome• Myopathy
Episodic:– Multiple sclerosis– Vascular malformation of spinal cord
Acute– Cord compression– Abcess– Spinal cord infarction – AV fistula / vascular anomaly– Transverse myelitis– Associated cerebral ischemia– Parasagital sinus / cortical Venous thrombosis– Acute hydrocephalus– Trauma
Approach to UMN WeaknessPlanter Upgoing
Yes No
Mono plegia LMN Lesion
Yes No
Fits Hemiplegia
Yes NO Yes No
(Lesion in Motor cortex) (Corona Radiata) Un crossed crossed Paraplegia
(internal capsule) Crossed
LMN VII N other cranial N
(Lesion
inbrainstem)