Paralysis due to brain disease The most common form is unilateral palsy, or HEMIPLEGIA, generally arising from cerebral HAEMORRHAGE, THROMBOSIS or EMBOLISM a?ecting the opposite side of the BRAIN. If all four limbs and trunk are a?ected, the paralysis is called quadraplegia; if both legs and part of the trunk are a?ected, it is called paraplegia. Paralysis may also be divided into ?accid (?oppy limbs) or spastic (rigid).
In hemiplegia the cause may be an abscess, haemorrhage, thrombosis or TUMOUR in the brain. CEREBRAL PALSY or ENCEPHALITIS are other possible causes. Sometimes damage occurs in the parts of the nervous system responsible for the ?ne control of muscle movements: the cerebellum and basal ganglion are such areas, and lack of DOPAMINE in the latter causes PARKINSONISM.
Damage or injury Damage to or pressure on the SPINAL CORD may paralyse muscles supplied by nerves below the site of damage. A fractured spine or pressure from a tumour may have this e?ect. Disorders a?ecting the cord which can cause paralysis include osteoarthritis of the cervical vertebrae (see BONE, DISORDERS OF), MULTIPLE SCLEROSIS (MS), MYELITIS, POLIOMYELITIS and MENINGITIS. Vitamin B12 de?ciency (see APPENDIX 5: VITAMINS) may also cause deterioration in the spinal cord (see also SPINE AND SPINAL CORD, DISEASES AND INJURIES OF).
Neuropathies are a group of disorders, some inherited, that damage the peripheral nerves, thus a?ecting their ability to conduct electrical impulses. This, in turn, causes muscle weakness or paralysis. Among the causes of neuropathies are cancers, DIABETES MELLITUS, liver disease, and the toxic consequences of some drugs or metals – lead being one example.
Disorders of the muscles themselves – for example, muscular dystrophy (see MUSCLES, DISORDERS OF – Myopathy) – can disturb their normal working and so cause partial or complete paralysis of the part(s) a?ected.
Treatment The aim of treatment should be to remedy the underlying cause – for example, surgical removal of a displaced intervertebral
disc or treating diabetes mellitus. Sometimes the cause cannot be recti?ed but, whether treatable or not, physiotherapy is essential to prevent joints from seizing up and to try to maintain some tone in muscles that may be only partly a?ected. With temporary paralysis, such as can occur after a STROKE, physiotherapy can retrain the su?erers to use their muscles and joints to ensure mobility during and after recovery. Patients with permanent hemiplegia, paraplegia or quadraplegia need highly skilled nursing care, rehabilitative support and resources, and expert help to allow them, if possible, to live at home.