UPWARD LUXATION OF THE PATELLA. 961 



sistent luxation usually cease to occur as the general condition 

 improves. 



Treatment. Young animals and convalescents should be well 

 fed and kept from heavy work. With rest and the recumbent position, 

 the straight ligaments of the patella return to their normal length. 

 Everything likely to cause relapse must be avoided. In momentary 

 luxation nothing further, except blistering the stifle, can usually be 

 done, but stationary luxation calls for immediate reduction, which 

 may be effected in one of several ways. 



(1) The patella often returns to its proper position after sudden 

 backward or side movements. Energetic contraction in the patellar 

 muscles, produced by an unexpected blow or by drenching the animal 

 with cold water, also induces reduction at times. 



(2) Where the above means prove insufficient, an attempt should 

 be made to free the lower edge of the patella by pressing on its upper 

 and outer border, the pressure being directed backwards and inwards. 



Meyer advised grasping the patella with the hand and lifting it 

 up whilst the animal was led forwards. 



Reduction is assisted by passing a cord round the fetlock, lifting 

 the toe from the ground, and drawing it forward, thus forcing extension 

 of the stifle-joint. The animal is then thrust backward, and at 

 the same moment the patella pushed back. Where the animal is 

 lying, the limb can be drawn forward and fastened as for castration, 

 replacement being attempted in this position. In order to induce 

 muscular relaxation chloroform should be administered. 



After successful reduction, the animal may be rested for a few 

 days ; in exceptional cases a longer rest may be prescribed. The 

 application of blisters, etc., to the stifle is only useful in keeping the 

 limb at rest. If the patella again slips upwards when the animal 

 lies down or rises, slinging may be resorted to, the affected limb 

 being prevented from moving backward by a sideline attached to 

 the pastern and secured round the neck ; or a shoe with a toe-prong 

 may be applied. Another useful device for recurrent luxation is a 

 patten shoe with deep staple, by which the limb is raised from the 

 ground, and the stifle-joint is kept semi-flexed, so that the conditions 

 necessary to upward luxation cannot well occur. 



Bassi and others recommended section of the inner straight 

 patellar ligament, and state having cured cases of repeated upward 

 luxation which had existed for years. The operation is, however, 

 by no means free from risk, because the inner straight ligament is 

 in close proximity to the capsule of the joint, but by dividing the 

 ligament near to its insertion on the tibia, where an abundant fatty 

 ii s. 3 Q 



