Electro-therapeutics, or, Electricity in its relation to medicine and surgery.

  • King, William Harvey, 1861-1942.
Date:
[1889], [©1889]
Catalogue details

Licence: Public Domain Mark

Credit: Electro-therapeutics, or, Electricity in its relation to medicine and surgery. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    cause in the motor nerve or in the gray anterior columns. If the disease is due to the former, only those muscles supplied by it exhibit R. D.; but, if the latter are the seat of disease, we are very apt to have R. D. in muscles supplied by more than one nerve. This brings it down to a very few diseases, and these can be easily distinguished by other diagnostic points. After carefully studying the preceding pages, one can plainly see that valuable deductions can be drawn from abnormal re- actions in regard to prognosis. It should be understood that in all grades of R. D., from a slight modal change to a complete loss of reaction, in the same disease and due to the same causes, the disease will be found to be of longer duration and in every respect more severe the later the stage of the disease in which it is found and the more complete is R. D. Methods of Determining Qualitative and Quantitative Changes.—A well-practiced eye can determine very accurately any qualitative change, or it can be done by comparison with other muscles on the same individual, as the muscles in differ- ent parts of the body, so far as their qualitative reactions are concerned, are about the same. First examine a healthy mus- cle on some other part of the body and note its quick, jerky contractions. Then compare it with the diseased one, and, if there is a modal change, it will be found that the muscle rises to its maximum of contraction more slowly; it remains at the summit of contraction longer, and declines slower than does the healthy muscle. Again, cause the healthy muscle to con- tract at ca. cl., an. cl. and an. o., and carefully note the num- ber of milliamperes it requires for each. Compare the same with the diseased muscle. If there is a serial change, it will be noticed that the difference in the number of milliamperes required to cause contraction is less according to the amount of R. D. that is present. It should be remembered that, when more than one motor nerve enters a muscle, and only one of the nerves is diseased, only that part of the muscle which is supplied by the diseased nerve will show changes in reaction. With the quantitative change one can never become so well practiced as to be able to determine it unless it is well marked, and it will not do to compare any two persons; therefore, we must take some more accurate method of comparison. I wish