DISEASES OF THE HORSE. 339 



appears to be much longer than the other, owing to the straightened 

 position of the thigh bone, which forms ahiiost a straight line with 

 the tibia from the hip joint down. The stifle joint is motionless, and 

 the motions of all the joints below it are more or less interfered with. 

 External examination of the muscles of the hip and thigh reveals a 

 certain amount of rigidity, with perhaps some soreness, and the stifle 

 bone may be seen projecting more or less on the outside and upper 

 part of the joint. 



This state of things ma}^ continue for some length of time and until 

 treatment is applied, or it may spontaneousl}' and suddenly terminate, 

 leaving everj-thing in its normal condition, but perhaps to return 

 again. 



Cause. — Pseudodislocation of the patella is likel}^ to occur under 

 many of the conditions which cause actual dislocation, and j-et it ma)^ 

 often occur in animals which have not been exposed to the ordinary 

 causes, but which have remained at rest in their stables. Sometimes 

 these cases are assignable to falls in a slippery stall, or perhaps slip- 

 ping when endeavoring to rise; sometimes to weakness in convalescing 

 patien ts ; sometimes to lack of to!iicity of structure and general debility ; 

 sometimes to relaxation of tissues from want of exercise or use. A 

 straight leg, sloping croup, and the 3^oung are predisposed to this 

 dislocation. 



Treatment. — The reduction of these displacements of the patella is 

 not usually attended with diflicult}-. A sudden jerk or spasmodic 

 action will often be all that is required to spring the patella into 

 place, w^hen the flexion of the leg at the hock ends the trouble for the 

 time. But this is not always sufiicient, and a true reduction may still 

 be indicated. To effect this the leg niust be drawn well forward by a 

 rope attached to the lower end, and the patella, grasped with the hand, 

 forcibly pushed forward and inward and made to slip over the outside 

 border of the trochlea of the femur. The bone sudden]}^ slips into 

 position, the excessive rigor of the leg ceases with a spasmodic jerk, 

 and the animal may walk or trot away without suspicion of lameness. 

 But though this may end the trouble for the time, and the restoration 

 seem to be perfect and permanent, a repetition of the entire transaction 

 may subsequently take place, and perhaps from the loss of some pro- 

 portion of tensile power which would naturall}^ follow the original 

 attack in the muscles involved the lesion might become a habitual 

 weakness. 



Warm fomentations and douches with cold water will often promote 

 permanent recovery, and liberty in a box stall or in the field will in 

 man}" cases insure constant relief. The use of a high-heeled shoe is 

 recommended b}" European veterinarians. The use of stimulating 

 liniments, with frictions, charges, or even severe blisters, ma}" be 

 resorted to in order to prevent the repetition of the difficulty by 

 strengthening and toning up the parts. 



