Hypothyroidism causes neurological dysfunctions like peripheral & entrapment neuropathy, cerebellar ataxia, myxedema coma etc¹. Studies show that motor symptoms increases with increase TSH levels. Nerve conduction study when conducted early in the course of disease helps in medical management of neuropathies before starting surgical treatment. This study assessed median motor parameters in recently diagnosed and untreated hypothyroid patients.

Objectives: To study the correlation between TSH values and median motor nerve parameters in newly diagnosed hypothyroid patients

Material & Methods: 270 hypothyroid males and females with age 20 to 50 years were included. Patients with neurological disorders, diabetes mellitus, those taking drugs causing neuropathy, alcoholics and smokers were excluded. Study design was descriptive All patients underwent electrophysiological studies in the department of Neuromedicine, GTDMC, Alappuzha for one year.

Study variables were distal latency, conduction velocity and amplitude of median motor nerve, TSH, fT3 & fT4. Median motor nerve parameters were correlated with TSH values and the results analysed statistically by SPSS software.

Results: Datas were analysed with SPSS version 18 using student t test and chi square test and p value <0.05 was considered as significant. Observations were represented both graphically and numerically.

Conclusion: In this study, strong association was found between TSH values and altered motor nerve parameters especially in distal latency. It may be due to entrapment neuropathy where deposition of mucinous substances around the peripheral nerves occurs. Early diagnosis and treatment can prevent the impairment of motor conduction parameters.

Keywords: Hypothyroidism, median nerve, Nerve conduction study.

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Dr Sinu Sankar M

Third year PG, Physiology, Affiliated to TCMC