Objective: To investigate the occurrence, degree, and risk factors associated with arthroscopic stifle joint synovitis in dogs with cranial cruciate ligament (CCL) disease.
Study design: Retrospective, observational study.
Sample population: Canine CCL disease (n = 163) from 149 dogs and their arthroscopic video recordings.
Methods: Arthroscopic video recordings were reviewed. A synovitis severity (0-5) and a modified Outerbridge cartilage classification system score were assigned, along with recording the presence or absence of a medial meniscal bucket handle tear. Medical records were reviewed for age, sex, limb, and duration of clinical signs. Univariate analyses were performed via a Fisher's exact test for categorical independent variables, and ordered logistic regression was used for continuous variables. Multivariable ordered logistic regression considered independent variables with a p-value <.2 on univariate analyses. p-value <.05 was considered statistically significant.
Results: Synovitis was identified in 100% of the stifles examined. The most frequent synovitis severity score was 3/5. Univariate analysis showed a significant association between synovitis severity score and bodyweight (p = .005), median cartilage score (p = .002), and being female (p = .032). On multivariable analysis, the synovitis severity score was significantly associated with median cartilage score (p = .042) and duration of clinical signs (p < .001).
Conclusion: Synovitis was arthroscopically always identified in stifles with CCL disease. The severity of synovitis was associated with more progressive damage to the articular cartilage and a longer duration of clinical signs.
Clinical significance: Earlier intervention in dogs with CCL disease may be warranted to decrease synovitis and progression of osteoarthritis.
