Victor Horsley’s experimental contributions to the study of myxoedema and cretinism
Sherry GINN1 and Joel VILENSKY2
Whereas Sir Victor Horsley is well known for the many contributions he made to neurosurgery, less well known are his to the treatment of both myxoedema and cretinism. Osler’s 1916 obituary of Horsley notes that a “direct result of his experimental work on the thyroid gland was the successful treatment of myxoedema, which for the first time placed organo-therapy on a scientific basis” (British Medical Journal 2:162-167, 1916). Horsley’s experiments on thyroid physiology extended from 1884 – 1890, while he was Director of the Brown Institute. Through direct experimentation with dogs and monkeys as well as selected experiments on human patients, Horsley demonstrated conclusively that removal of the thyroid gland produced both conditions, a fact generally not recognized before this time. Horsley’s comparison of surgical removal of the thyroid showed differential effects on the species tested, with animals such as monkeys exhibiting symptoms similar in onset and duration to humans. Horsley reported that removal of the thyroid gland resulted in nervous symptoms. Among these were tremors, rigidity and paralysis resulting from changes in the lower motor centers. Furthermore, the development of imbecility suggested that thyroid excision produced deficits in higher cortical functioning. Specifically, he stated that “slow hebetude ending in varying degrees of imbecility with easy disturbance of temper were the disorders related to the cortex of the brain” (Lancet: 1133, 1884). Horsley showed that it was possible to alleviate some of the psychological and physiological symptoms of both myxoedema and cretinism using transplanted thyroid tissue. Although these transplants were not always successful, several of Horsley’s students, notably George Murray, continued and extended his work by examining other ways in which myxoedema and cretinism could be treated (e.g., injecting an extract of thyroid tissue).
Tenth Annual Meeting of the International Society for the
History of the Neurosciences (ISHN) and
St. Andrews, Scotland, 2005