512 VETERINARY SURGICAL OPERATIONS 



Hygroma of the Knee. 



Bruise of the knee from falling upon hard streets without 

 solution of continuity of the skin causes an "acute hygroma," 

 a serous sac or a sanguineous sac that appears in the form of 

 a large fluctuant enlargement, slightly painful at first but 

 finally sojourning for weeks, and even months, in the ab- 

 sence of all pain and inflammation. In rare cases they be- 

 come purulent and then cause considerable pain until the 

 pus is evacuated. 



Hygroma of the knee is seen chiefly in draft horses, al- 

 though the lighter breeds sometimes sustain it. It is 

 caused by slipping, usually when starting a heavy load. 

 The toe calk fails to hold, the foot slips backward and the 

 knees strike the street violently. The accident occurs 

 quickly, often entirely unnoticed by the teamster. It is 

 rarely bilateral at first, although both knees may sustain the 

 injury consecutively. 



The trend of this lesion is toward permanent tumefaction 

 of the knee, either by thickening of the skin or by the forma- 

 tion of a chronic hygroma. In either case the blemish is 

 permanent. 



TREATMENT.— The greatest obstacle in the treat- 

 ment of knee bruises of this variety is the constant repeti- 

 tion of the accident. While it may sometimes be directly 

 attributed to insufficient calking during the slippery sea- 

 son more often it is an habitual fault of the horse, which 

 will continue to injure the half healed sac of a former acci- 

 dent, and thus prevent cicatrization. 



To successfully cope with the affliction absolute rest of 

 four weeks is required, for if the animal is kept at work the 

 enlargement becomes chronic. 



To effect a perfect cure the sac is evacuated by lancing 

 inferiorly, after having shaved and disinfected the seat of 

 operation with due thoroughness. The opening should be 

 no longer than one-half inch. The bleeding, which usually 

 consists of a spurting vessel or two in the skin on each side 

 of the incision, is arrested by touching up the spots with 

 the thermo-cautery. The opening is then wadded snugly 

 with a small cotton pledget soaked in a strong antiseptic, 

 and the leg placed in a brace (Fig. 258) for ten days to two 

 weeks. At first twice per day and later once daily the wad is 

 removed and the accumulated secretion gently pressed out. 

 At the end of two weeks the horse is given gentle exercise 



