Clinical and radiographic results of total hip arthroplasty in dogs: 96 cases (1986-1992).

Results of total hip arthroplasty in 84 dogs (96 hips) were evaluated. Eight (9.5%) of the 84 dogs developed 1 or more complications after total hip arthroplasty. Complications resolved or were corrected in 4 of the dogs; all 4 ultimately achieved good or excellent hip function. Complications necessitated removal of the prosthesis in the other 4 dogs; 3 ultimately achieved fair hip function and 1 had only poor hip function. Therefore, after resolution of complications, 96% of the hips had good or excellent function. Force plate analysis was performed on 6 dogs with excellent hip function; peak vertical force for the limb that had been operated on was greater than or equal to peak vertical force for the contralateral limb. Radiographically, a radiolucent zone was visible around the acetabular component in 89% of the hips and around the femoral component in 26%. The radiolucent zone around the acetabular and femoral components widened in 14% (6 of 43) and 27% (3 of 11), respectively, of the hips with adequate radiographic follow-up. Aseptic loosening of the acetabular component developed in 3 (3%) of 96 hips; one was successfully revised. Aseptic loosening of the femoral component was not apparent in any of the dogs in this study. Other complications included femoral fracture (n = 3), neurapraxia (3), luxation (1), and unexplained lameness that required implant removal (1). None of the dogs had evidence of wound infection.