Preoperative variables affecting long-term outcome of triple pelvic osteotomy for treatment of naturally developing hip dysplasia in dogs.

OBJECTIVE

To determine whether preoperative radiographic evidence of degenerative joint disease (DJD), hip joint laxity, or age at surgery is associated with long-standing DJD or hip function in dogs with hip dysplasia (HD) that had a triple pelvic osteotomy (TPO).

DESIGN

Prospective study.

ANIMALS

34 dogs with HD.

PROCEDURE

Dogs that had TPO performed during an 8-year period were chosen for long-term follow-up evaluation that included physical examinations, pelvic radiographs, and owner questionnaires. Data on radiographic evidence of DJD, Norberg angle, and percentage of femoral head coverage were retrieved from preoperative records and determined from follow-up radiographs.

RESULTS

Approximately 40% of dogs had progression of DJD. Eighty-seven percent of dogs received excellent or good physical examination scores, and 76% received excellent or good at-home activity scores. Preoperative and long-standing DJD were not associated. The risk of DJD was increased with increased age at surgery, narrower preoperative Norberg angle, and lower percentage of femoral head coverage, but these variables were not associated with clinical hip function.

CLINICAL IMPLICATIONS

TPO for treatment of HD in dogs may slow, rather than stop, radiographic progression of DJD; however, clinical outcome is acceptable for most dogs. Preoperative evidence of DJD may not be a limiting criterion in selecting dogs as suitable TPO candidates. Dogs with extensive hip joint laxity before surgery may be predisposed to developing DJD; thus, the risk-to-benefit ratio for TPO versus salvage procedures should be considered. Younger dogs may develop less severe DJD after TPO; surgery should be considered at the first sign of hip joint laxity and pain.