| This research program was designed to evaluate new and established diagnostic techniques to assess the severity and progression of osteoarthritis (OA) in a canine hip dysplasia model. Puppies predisposed to hip dysplasia were evaluated over a period of 30 months. Hip radiographs were taken and synovial fluid collected from each joint at six intervals during the course of the study. Computed tomography (CT) scans were performed during the final evaluation (120 weeks of age), and cartilage from each hip was evaluated histologically for OA. Radiographs from each time interval were scored for the presence of OA. Synovial fluid was analyzed with the monoclonal antibody OA markers 3B3(−) and collagen II 3/4C-long. A series of measurements were made on radiographic and two- and three-dimensional CT images performed at 120 weeks of age.; There was a significant negative linear correlation between levels of 3B3(−) and age, and a weak but significant positive linear correlation between COL2-3/4C long levels and age. There were also linear relationships between radiographic and histologic OA scores at 120 weeks and levels of both markers beginning at 24 weeks of age. Levels of COL 2-3/4C long for each final OA score remained fairly steady over time. 3B3(−) levels decreased in joints that remained healthy. As the final OA score increased, the levels were less variable over time. Measurements on standard hip radiographs (Norberg angle and femoral head coverage) had strong linear correlations with OA. Values measured on two-dimensional CT images (CE, HTE, AASA, and HASA angles, acetabular index and femoral head coverage) had moderate to strong linear correlations with OA. On three-dimensional CT images, dorsoventral acetabular shelf/femoral head ratio had good linear correlations with radiographic OA, but not with histologic OA.; The use of synovial fluid OA markers and CT for distinguishing OA severities in canine hips for research and clinical purposes may set new standards by which canine hips are evaluated. Information from this study may prove useful when used in conjunction with other methods of canine hip evaluation, and may pave the way for similar analyses in children predisposed to developmental dysplasia of the hip. |
