A stroke occurs when the blood supply to part of your brain is interrupted or severely reduced, depriving brain tissue of oxygen and nutrients. Within minutes, brain cells begin to die

Causes :

Many conditions give rise to hemiplegia. Generally, an injury to the right side of the brain will cause a left-sided hemiplegia while an injury to the left side of the brain will cause a right-sided hemiplegia.

Stroke: is the commonest cause of hemiplegia. Insufficient blood supply to the brain leads to loss of brain functions. The stroke may be caused by: A clot formed within the blood vessel blocking the blood supply (Thrombus). Thrombus breaks away from its site of origin and forms a block elsewhere in the circulation (an Emboli). A bleed from a blood vessel supplying the brain (Hemorrhage) which can be caused by

Head injury

Diabetes

Brain tumor

Infections like Meningitis, Encephalitis

Migraine syndrome -> recurrent headaches of severe intensity occasionally accompanied by sensations of numbness and tingling in one half of the body.

Inflammation of the blood vessels -> vasculitis

Diseases affecting the nerves like Multiple Sclerosis; acute necrotizing myelitis.

Conditions presenting from birth like cerebral palsy. Lack of blood supply damages nerve cells in the brain. Birth trauma, difficult labor, perinatal strokes in infants within 3 days of birth can all cause cerebral palsy.