Additional experiments on the excitability of paralysed and healthy limbs by the galvanic current / by R. B. Todd, M.D., F.R.S. (Physician to King's College Hospital).

  • Todd, R. B.
Date:
1853
Catalogue details

Licence: Public Domain Mark

Credit: Additional experiments on the excitability of paralysed and healthy limbs by the galvanic current / by R. B. Todd, M.D., F.R.S. (Physician to King's College Hospital). Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

    7/26 (page 5)
    between the contractions of the limb in which the current is inverse and those of the limb in which the current is direct. 3. After the nerves have been removed, the limbs no longer exhibit those differences in the influence of the in- verse and direct current first noticed by the Italian physi- ciens, such as the excitation of contractions on completing the direct current, or interrupting the inverse. 4. After the nerves have been removed, the excitability of the limbs by the current ceases in each at the same moment. 5. The removal of the nerves prevents the development of that remarkable phenomenon,—the sudden assumption, on breaking the circuit, of the tetanoid state by the muscles of a limb through which the inverse current has passed for some time without interruption. I shall now proceed to narrate a few experiments made upon paralytic patients, in which greater precautions were taken than in my former experiments, both with reference to the direction of the current and to other points, which will appear in the account of each experiment. Case i.—April 14, 1848. My friend Dr. Walshe, of University College Hospital, kindly permitted me to compare the excitability to galvanism of the healthy and paralysed limbs in a patient who was suffering from hemiplegia, and he also lent me his valuable assistance in the experiments. The patient was an old woman, who had suddenly be- come completely paralysed on the right side; the muscles of that side were perfectly relaxed, and presented not the slightest rigidity : they were softer than those of the sound side, and appeared to have experienced a slight degree of wasting. The seizure was not preceded by any premonitory symptoms. The first trials were made with a Cruickshank's battery. The current was passed only through the upper extremi- ties, as it was found inconvenient to include the lower ex- tremities. I shall give the results in the following tabular form,