Neurologic and Muscular Manifestations of Hyperthyroidism

Development of neurologic or muscular manifestations in the course of hyperthyroidism was well recognized by investigators of the nineteenth century. Numerous reports are now available in the literature concerning a number of such syndromes. In most cases there is a weakness of peripheral or cranial musculature often associated with variable degrees of muscular atrophy. Sattler104in 1908 presented the most valuable review of the older literature of thyrotoxicosis and its neurological and muscular complications. Recent classifications have included primarily muscular syndromes in the form of acute and chronic myopathies, ophthalmoplegia, myasthenic syndromes, and periodic paralysis.16,73,80,111,117Since these classifications do not include all neurological and muscular complications described to date, the following scheme is offered for complete coverage of the subject: A. Myopathies Resulting from Hyperthyroidism 1. Acute thyrotoxic myopathy 2. Chronic thyrotoxic myopathy 3. Endocrine ophthalmoplegia B. Myopathies Sometimes Associated with Hyperthyroidism but Probably of Independent Origin