On paralysis agitans : with an account of the clinical features of other forms of tremor / by R. T. Williamson.

  • Williamson, R. T. (Richard Thomas), 1862-1937.
Date:
1901
Catalogue details

Licence: In copyright

Credit: On paralysis agitans : with an account of the clinical features of other forms of tremor / by R. T. Williamson. Source: Wellcome Collection.

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    subsides when the alarm is over, but it has been known to persist and develop into this disease, or the tremor may commence a day or two after the shock.” It is probable when paralysis agitans develops after a severe fright that the latter has sometimes only acted as the last factor, the exciting cause, or the accelerating factor in the causation of the disease, and that some pathological changes have been already present in the nervous system. Of the many persons who suffered from severe mental shock, fright, anxiety, &c., only very few develop paralysis agitans. Hence it is probably that there is some predisposing cause or additional factor in the production of the disease. Further, in many cases, no definite history of fright can be obtained. The cases on record are sufficient to show, however, that fright and mental anxiety (psychical trauma) are important antecedents or etiologial factors in the causation of the disease in many cases. They are the most important causes at present known to us. Mechanical trauma is occasionally the exciting cause of the disease. Often there has been great mental shock in addition to the injury. Krafft-Ebing records seven cases of traumatic origin amongst i io cases of paralysis agitans. Walz has analysed a number of cases recorded in medical literature. The nature of the injury was as follows: General concussion in six cases, wounds in seven, burns in one, frost-bite in one, sprains, disloca- tions, and fractures in four, contusions and injuries of indefinite nature in eight. In eight of the cases analysed by Walz the tremor commenced immediately after the accident, or within the first day. As paralysis agitans follows an injury so exceedingly rarely, there must be some predisposition to the disease, or some additional factor besides the injury in its causation. There is, however, distinct evidence that in certain cases mechanical injury has been an exciting cause. In these cases the tremor has commenced in the part injured, and this fact shows that the injury is not simply a coincidence. Krafft-Ebing has recorded cases in which local overstrain appears to have been an important factor in the causation.