Pattern of motor neurone disease in eastern India

A clinical study about the pattern of motor neurone disease in eastern India was carried out from July 1993 to June 1995 at Bangur Institute of Neurology, Calcutta and SSKM Hospital, Calcutta. A total of 110 cases were studied and they constituted 0.11% of all neurological cases seen in the general OPD. Of 110 cases, amyotropic lateral sclerosis (ALS) constituted 43.6%, progressive muscular atrophy (PMA) 10.9%, post-polio progressive muscular atrophy (PPMA) 1.8%, spinal muscular atrophy (SMA) 20%, atypical form Madras pattern of MND (MMND) 0.9% and monomelic amyotrophy (MMA) 22.7% of cases. Disease is more common in males than females and average duration of symptoms before presentation varied from 1 to 12 months. Most of the patients were either agricultural labourers or manual workers in ALS variety whereas MMA variety was evenly distributed in both hard labourers and sedentary workers. Most of the patients in MMA and SMA groups presented before 30 years of age whereas ALS and PMA group presented after 30 years. Trauma was the commonest antecedent event in ALS and MMA followed by electrocution in the same two groups. Family history was found to be absent in SMA group though the disease is considered as a hereditary one. Weakness of the limbs and wasting of the muscles were common presenting symptoms and signs. Bulbar symptoms and signs were found only in the ALS group. EMG showed neurogenic pattern and mixed pattern in most of the patients in all groups. Only a few patients showed myopathic pattern. Neuroimaging study helped in exclusion of compressive lesion excepting two cases of MMA where facetal hypertrophy was present. Monomelic amyotrophy, a special variety of motor neurone disease, is not rare in this part as compared to other parts of India and Asia.