The diagnosis of diseases of the spinal cord.

  • Gowers, W. R. (William Richard), 1845-1915.
Date:
1880
Catalogue details

Licence: Public Domain Mark

Credit: The diagnosis of diseases of the spinal cord. Source: Wellcome Collection.

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

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    to theii- degeneration, since the fibres only conduot, and do not originate nerve force. The pyramidal fibres enter the grey substance, and apparently end in its interlacing network of fine fibres and minute nerve cells, and by means of this structure are connected with the large ganglion cells of the motor nerves. The phenomena are best explained by the hypothesis that this structure, in the matiix of the grey matter, controls the miiscle-reflex centres (of which the ganglion cells are part), and that the degeneration of the pyramidal fibres, which can be traced to the grey matter, invades this structure. The loss of its influence permits the over-action of the muscle- reflex centre. The foot-clonus can often be obtained in sHght chloroform narcosis, but under the full action of chlorof onn it disappears; apparently this agent in- fluences the controlling structure before it influences the muscle-reflex centres. Ether and nitrous oxide do not abolish myotatic irritability (Horsley). After an epileptic fit, again, a clonus can be obtained for a few minutes, while after a very severe fit, the myotatic irritability, instead of being increased, may for a few seconds be lost, so that not even the knee-jerk can be obtained. In the first case the discharge appears to temporarily exhaust the controUing structiu'e; in the second, the more severe action exhausts also the muscle-reflex centre itself.* It is uncertain whether we should ascribe all over-action of these centres to loss of control. We are justified in doing so when the over-action follows permanently a destroying lesion, such as the degeneration of the lateral columns. SHght over-action is sometimes present when there is no * I do not know of any pathological observations of tlie state of the ^ matrix of the grey substance when there is degeneration of the lateral columns without a£Peotion of the motor ganglion cells. The investigation is very difficult on account of the character of the structure. In cases so extremely rare as to be manifestly exceptional in mechanism, the foot-clouus has been observed a few hours after the onset of hemiplegia. It is probable that in these cases the controlling structure is inhibited by the ii-ritation of the cerebral lesion. A case lately seen suggests that the knee-jerk may even be lost during the first hour after the onset, and then return : the UTitative inhibition extending to the muscle-reflex centre itself.