Diseases of the spine and of the nerves / By C.B.R., John Netten Radcliffe, J.Warburton Begbie, Francis Edmund Ainstie and John Russell Reynolds.

  • Radcliffe, Charles Bland.
Date:
1871
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of the spine and of the nerves / By C.B.R., John Netten Radcliffe, J.Warburton Begbie, Francis Edmund Ainstie and John Russell Reynolds. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    boundaries of the pyramids. If anaesthesia be the result of cutting across the anterior pyramids of the medulla oblongata, its amount is too small to be unequivocal; and, in a word, all the evidence, old and new, goes to show that these bodies are composed of conductors con- cerned in voluntary motion without any admixture of sensory con- ductors. The office of the lateral columns of the spinal cord is not so clearly made out as that of the posterior and anterior columns. In the cervi- cal region, for a short distance below the point at which the anterior pyramids of the medulla oblongata intercross, the lateral columns of the spinal cord have certainly very much to do in transmitting the orders of the will to the muscles; for, as has just been seen incidentally, the muscles behind the section on the same side of the body are para- lyzed by cutting one of them across. In the lower part of the cervical region, and in the dorsal and lumbar regions, it is very different, and the difference is not very clearly determined. Here some trifling para- lysis may be produced by dividing these columns transversely, but never more than this. Here, indeed, it would seem that this operation is followed by a certain degree of anaesthesia, and by the same result, as regards movement, as that which follows transverse division of the posterior columns—that is, not by paralysis, but by in-coorclination. A certain degree of anaesthesia appears to be a constant consequence of cutting across the lateral columns in any part of their course ; and herein would seem to be an important distinction between the lateral and the posterior columns, for, as has been stated already, the result of cutting across the posterior columns is to produce hyperesthesia, not anaesthesia. A section of the olivary bodies is followed, not by any marked degree of paralysis, or anaesthesia, but by a state of persistent spasm in many muscles on the same side of the body, in the neck especially—a state which may sometimes continue for days, weeks, or even months. It is found, also, that this strange result is produced by irritating several parts of the base of the encephalon, the lateral and posterior parts of the medulla oblongata and pons Varolii especially, as well as by irrir tating the olivary bodies. These parts are not very clearly defined. They seem, says Dr. Brown-Sequard, to be quite different from those employed in the transmission of sensitive impressions, or of the orders of the will to the muscles, at least in the medulla oblongata and pons Varolii. They constitute a very large portion of these two organs, and, perhaps, as much as three-fourths of the one first named. They are placed chiefly in the lateral and posterior columns of these organs ; and because many of their fibres do not decussate, the spasm produced by irritating them is on the same side of the body. Instead of being merely a nerve centre—the special centre of Mar- shall Hall's excito-motor system of nerves—there is now reason to believe (as Dr. Brown-Sequard has so clearly shown), that the gray substance of the spinal cord is an important conductor of sensory and motor impressions. Paralysis without loss of sensation on the same side of the body, loss of sensation without paralysis on the other side of the body, are the strange results of cutting across one lateral half