ENLARGEMENT OF SYNOVIAL CAVITIES IN FORE LIMB. 559 
sheath undergoes slow thickening and its contents become absorbed, 
success or failure appearing particularly to depend on the degree of 
inflammation produced by the injection. It is best to use a freshly- 
prepared solution of iodine, to see that it is completely removed after 
injection, and to follow this with a blister or with firing ; when blistering 
is contra-indicated, a tight bandage may be substituted. To test the 
relative danger of iodine injections, Leblanc and Thierry made a series 
of thirty-two ;—fifteen into joints, seven into mucous bursas and ten into 
tendon sheaths, without in any case having bad results. Needless to say, 
they observed full antiseptic precautions. In general, this treatment is 
uncertain, and when the enlargement is indurated, impossible. Masses of 
fibrin can only be removed by operation, and although in theory such 
operation should not be dangerous if performed under aseptic precautions, 
yet there is no certainty that dressings will remain in position; even 
when the preliminary dressing, applied for the purpose of sterilising the 
parts, has not been interfered with, dressings applied after operation 
are often violently rubbed off. The same is true in regard to animals 
other than the horse. The opening of distended joints or flexor tendon 
sheaths is in general dangerous, though there seems no particular risk in 
opening extensor sheaths, even when the parts cannot be kept aseptic. 
The risk need not prevent operation being tried, but attention should 
certainly be previously directed to the danger, and the strictest antisepsis 
should be observed. With this object, twenty-four hours beforehand, 
the hair is shaved from the point of operation, the skin washed, and a 
dressing moistened with 1 per 1,000 of sublimate applied. After casting 
the horse for operation and removing the dressing an incision is made, 
under antiseptic precautions, at the highest point of the swelling ; the 
finger is then introduced, the condition of the sheath examined, and any 
masses of fibrin, &c., removed. The cavity is washed out with a solu¬ 
tion of iodine and iodide of potassium in water (1:3:16), followed by 
sublimate or carbolic solution. The loose distended skin can then be 
partly cut away in an elliptical form, the wound closed with silk, and a 
dressing applied to keep out air and to exercise pressure. This dressing- 
should not be changed for about eight days. The wound probably closes 
in three to four days, though the cicatrix is not then sufficiently firm to 
prevent re-opening if the animal be moved. Operating in this way Lies 
cured a large wind gall (enlarged sesamoid sheath) and an enlargement of 
the precarpal sheath of the extensor pedis tendon which had resisted all 
ordinary methods of treatment. In enlargements of the extensor sheaths 
setons may be used, but Moller prefers operation. 
Bosco has recommended opening enlarged tendon sheaths with the 
red-hot iron, and favourable results have since been announced from 
other quarters. The glowing point of a firing-iron is thrust into the 
