CONCUSSION OF THE BRAIN. 377 



(2.) CONCUSSION OF THE BRAIN (COMMOTIO CEREBRI). 



Concussion is induced in horses by falls or collisions, and less 

 frequently by kicks from a shod foot. Wilhelm diagnosed the 

 condition in a cow which had fallen a distance of 14 feet off a wall. 

 Dogs and cats suffer from falls from windows as well as from blows 

 on the skull. 



The symptoms consist of loss of consciousness, inability to 

 stand and walk, sometimes pallor of the mucous membranes, 

 and a small, infrequent pulse. In carnivora vomiting may be 

 present. Respiration is sometimes irregular. Various views are 

 held concerning the alterations produced in the brain : molecular 

 displacement is scarcely sufficient explanation, nor do the experi- 

 ments of Koch and Filehne demonstrate the precise pathological 

 conditions. 



Course. Where concussion is not associated with fracture of 

 the skull, bleeding into the cranial cavity, or further injuries, the 

 symptoms usually disappear in a short time, often after a few hours, 

 at latest after some days. A so-called reaction sometimes follows, 

 the mucous membranes become red, the pulse more frequent and 

 wiry — conditions indicating febrile mischief. 



Medical interference is usually contra-indicated, and if adopted 

 must be confined to treating symptoms. The drugs oftenest employed 

 are heart stimulants. 



Absolute rest and easily digestible food in moderate quantity 

 are desirable. In a case reported by Wilhelm, complete recovery 

 occurred after two days. 



(3.) FRACTURES OF THE FRONTAL BONE. 



When occurring in the upper portion, prognosis and treatment 

 are the same as in fractures of the skull. It is otherwise where the 

 wall of the frontal sinus or the external plate of the bone is alone 

 involved. Fractures here have a different signification according 

 to their position. In most cases the prognosis is favourable and 

 treatment successful, as experience in trephining the frontal sinus 

 would indicate. In ruminants, fracture of the frontal bone only 

 becomes serious when the inner plate of bone is affected ; then 

 treatment is similar to that in fractures of the skull. Fracture of 

 the horn core will be considered later. In those of the orbital process 

 of the temporal bone the eye may be endangered, as in fracture of 

 the orbital process of the malar bone, either on account of dislocated 



