LUXATION OF THE SACRO-ILIAC ARTICULATION. 739 



may be at first affected, the body-weight is apt to break down the 

 union between the sacrum and the ilium on the other side, or that 

 the inner angle of the ilium may become fractured ; the animal is 

 then unable to stand. Complete fracture through the ischio-pubic 

 symphysis in horses also appears to be incurable. 



Treatment. If treatment is attempted, complete rest is a primary 

 necessity. In most fractures of the external angle of the ilium, 

 it is sufficient to keep the animal from work for a time ; if unable 

 to stand on the foot of the affected side, the patient should be slung. 

 In some pelvic fractures (acetabulum, iliac or ischial shaft), the pre- 

 caution of slinging the patient is very necessary, because of the 

 grave risk of further displacement of the broken parts should the 

 horse lie down. Cases complicated by abscess, sinus formation, or 

 necrosis should be treated according to general surgical principles. 

 Perineal or pelvic sinus following pubic or ischial fracture with 

 necrosis is nearly always incurable ; the source of the pus cannot 

 be effectually treated, and though the horse may be free from 

 lameness and quite workable the tail and thighs during fast work 

 are constantly soiled with offensive discharge. 



In uncomplicated pelvic fractures patients, after resting six to 

 eight weeks, may be moved cautiously, but if unable to bear weight 

 on the foot of the affected side, they should be returned to slings. 

 Stiffness in movement is less important, because it depends to some 

 extent on the long rest, and gradually disappears with exercise. 

 Provided pain is not excessive, the muscles of the quarter and thigh 

 may be massaged to prevent that rapid atrophy which follows severe 

 lameness. Daily kneading of the parts will promote nutrition of 

 the muscles. Atrophy, being only due to inactivity, disappears 

 with return to regular work. An adhesive plaster or a charge is 

 often applied to the affected quarter with the object of restraining 

 movement. For this purpose and perhaps to hasten the ossifying 

 process some veterinary surgeons use blisters. 



V.— DIASTASIS OR LUXATION OF THE SACROILIAC 

 ARTICULATION. 



The union between the sacrum and ilium on each side is formed b} T 

 a stiff, almost immobile, joint, the short capsular ligament of which 

 envelops the whole articulation. The superior and inferior sacro-iliac 

 ligaments, assisted by the sacro-sciatic ligament, contribute to this union. 



In horses, this ligamentous apparatus unites the bones so firmly 

 that they are very seldom dislocated, it being easier to break the 



