This first affects vertical movements (initially only willed movements), and congugate lateral gaze involvement at a later stage. 5. Cerebral anoxia

degenerative condition of unknown etiology. It resembles Parkinsonism in the association of hypokinesia with hypertonus, differing from it in that it is associated with a diagnostic disorder of ocular motility. This first affects vertical movements (initially only willed movements), and congugate lateral gaze involvement at a later stage. 5. Cerebral anoxia - Diffuse cerebral anoxia resulting usually from cardiorespiratory arrest can lead to Parkinsonism due to bilateral basal ganglia infarction. In younger people severe hypotension wit.h hypoxia in opiate overdosage and carbon monoxide poisoning are the usual causes. G. Dystonia musculorum deformans (Torsion spasm) Disease of basal ganglia of unknown etiology characterised by occurrence of slow, strong, sustained, twisting, turning and writhing movements of the somatic muscles, particularly muscles of girdle and trunk Abnormal movements and spasm of muscles produce bizarre stepping gait and often dysarthria, facial grimacing and torticollis. 7. Spasmodic torticollis - Usually starts in adolescence or early adult life and characterised by marked tonic or clonic movements of sternomastoid, trapezius and other muscles of neck. This results in the neck being twisted to one side, the shoulder being elevated and sometimes, the head tilted backwards. The movements are intermittent, aggravated by emotion and anxiety and stop during sleep. Distinction between hysterical and organic torticollis may be difficult 20 HEREDITARY AND DEGENERATIVE DISORDERS Cerebral Palsy Definition - The term cerebral palsy refers to a variety of neurological deficits, permanent but nonprogressive, mainly affecting motor function, as a result of prenatal insult, birth injury or some illness in early infancy. In addition to motor defects, intellectual impairment is common Risk factors Prenatal - Malformations, obstructive lesions in the brain (e.g. cysts, peri ventricular leucomalacia), infection, exposure to toxins, genetic predisposition. Perinatal- Asphyxia, hemorrhage, low birth weight, prematurity. Postnatal - CNS infection and trauma. Clinical Features: SPASTIC - (a) Spastic hemiplegia - Commonest type. May be associated hemisensory and hemianopic visual field defect and sometimes dysphasia Seizures may occur. (b) Spastic diplegia - Difficulty in walking, scissor gait. Upper limbs relatively spared. (c) Tetraplegia - Equal involvement of all four limbs. Seizures likely, and primitive reflexes (tonic neck, Mora, sucking, grasping) persist well beyond normal age. Limbs may become spastic by end of first year. 2. EXTRAPYRAMIDAL -Choreoathetosis and dystonia. Associated difficulty in articulation, draolling and emotional lability. Usually normal intelligence. 3. ATAXIC- Cerebellar ataxia often associated with mental retardation. 4. MIXED SYNDROME - Combination of spastic paraplegia and ataxia. Investigation - (a) Intrauterine infection if under 3 years of age. (b) Chromosome analysis if features are dysmorphic or intrauterine growth is poor. (c) EEG if seizures. (d) Brain imaging to look for maldevelopment, atrophy, peri ventricular leucomalacia, or migration defects. Management: 1. Physiotherapy - to be started early. 2. Drugs - (a) Spasticity - Baclofen acts peripherally, dantralene has direct effect on muscle. (b) Dystonia - Diazepam, benzhexol, tetrabenzene. 3. Surgery- (a) Neurasurgical- Selective dorsal root rhizotomy. (b) Orthopoedic for structures and other deformities. Syringomyelia Definition - A chronic progressive disorder in which cavitation (syrinx = pipe) develops within the spinal cord, either involving the central canal, the central grey matter of the spinal cord