=Prognosis.= The prognosis varies greatly. If the luxation is of traumatic origin and the accompanying symptoms are not grave, reduction may be followed by permanent recovery. On the other hand, in spontaneous luxation recurrence is almost inevitable. =Treatment=. The indications for treatment may be comprised in a single phrase: reduction, with immobilisation of the parts for a sufficient time. To effect reduction, a strip of webbing is fixed around the pastern of the affected limb, passed over the withers, in front of the shoulder of the opposite side, and brought round in front of the neck or between the front limbs. By means of this an assistant exercises strong traction on the limb until the fetlock is raised as high as the elbow of the same side. The operator then applies strong inward pressure to the patella, which usually slips back on to the gliding surface of the trochlea at the first or second effort. [Illustration: $1] After-treatment comprises the application of a smart blister, producing œdematous infiltration of all the tissues around the joint, and thus impeding movement and recurrence of luxation. For this purpose various preparations are used—_e.g._, cantharides, biniodide of mercury, croton oil, etc. It is also advisable to fix the animal so that for a time it cannot lie down, and to secure the pastern to the neck by means of a side-line. As an experiment, cases of simple fixation of the patella on the summit of the internal lip of the trochlea might be treated by Bassi’s method—_i.e._, subcutaneous division of the internal lateral ligament of the patella which holds the bone in its abnormal position. Finally, in spontaneous luxation, occurring in young animals in which blisters have been ineffectually tried after reduction, Bénard’s bandage may be used, though it is not generally regarded as very practical. It consists of a piece of cloth of elongated lozenge form about four feet in length, six inches in breadth at its centre and two inches at its ends. Its centre is pierced by a transverse opening intended to surround the patella, and carries a loop for the purpose of supporting the turns of bandage. A second longitudinal opening is situated about eight inches from the centre. Reduction being effected, the whole region of the stifle joint is covered with Burgundy or ordinary pitch and the bandage then applied. The patella projects through the central opening. The end A is passed backwards around the thigh, and through the aperture B; the two cross ends are then brought forward, crossed again at the end, the loop over the patella carried a second time backwards, again crossed, and finally fixed in front under the patella. The bandage should be firmly applied, without, however, being so tight as to interfere with circulation, and must be left in place from eight to ten days. [Illustration: $1]