TRAUMATIC SYNOVITIS — "OPEN SYNOVITIS." 49 



probably consists in puncturing the parts with antiseptic precautions, 

 washing out the synovial cavity with an antiseptic, and immediately 

 afterwards lightly firing the surface of the region in points. 



DISTENSION OF TENDON SHEATHS IN THE REGION 

 OF THE KNEE. 



Any of the numerous tendon sheaths which facilitate the gliding of 

 tendons in the neighbourhood of the knee may become inflamed 

 and give rise to a chronic synovial swelling. The commonest of 

 such swellings is due to distension of the sheath of the extensor 

 metacarpi magnus, which appears as a vertical line in front of the 

 knee, extending from the lower third of the forearm and slightly to 

 the outer side of the central line. This synovial enlargement arises in 

 oxen working on broken roads, in clay or marshy soils, where the 

 animals are liable to stick fast, and are often obliged to struggle 

 vigorously in order to extricate themselves. 



The diagnosis is based on the position and direction of the dilated 

 synovial sheath. 



Treatment is identical with that of other cases of chronic synovitis. 



DISTENSION OF THE BURSAL SHEATH OF THE FLEXOR 

 TENDONS. 



This condition is rare. It is announced, as in the horse, by a 

 dilatation of semi-conical form, the apex of which is situated opposite the 

 lower margin of the carpal sheath, the base extending as high as the 

 infero-posterior third of the radius. 



The dilatation is more marked on the inner than on the outer side 

 of the limb. 



Distension of the synovial sheath of the common extensor of the 

 digits in the fore limb and of the extensor of the external digit is still 

 rarer than the preceding conditions. 



TRAUMATIC SYNOVITIS-" OPEN SYNOVITIS.'^ 



When an injury in the neighbourhood of a joint penetrates deeply, it 

 may implicate either the synovial sheath of a tendon or the synovial 

 membrane of a joint. If the body inflicting the wound is aseptic, a 

 condition which in accidental wounds is rare, the w^ound may have no 

 grave consequences. Usually, however, the body producing the injury 

 is infected, and the infection rapidly extends throughout the tendon 

 sheath or synovial sac. In the first case, traumatic suppurating synovitis 

 of a tendon sheath is the result ; in the second, a suppurating articular 

 synovitis arises, which soon becomes complicated with injury of the 

 articular cartilages, ligaments, etc. (traumatic arthritis). 



D.c. E 



