Objective The aim of this study was to determine the trochlear sulcus depth of three common brachycephalic breeds at risk of medial patellar luxation.

Study Design Retrospective blinded clinical study using a previously validated ratio (T/P) of maximal trochlear sulcus depth (T) and maximal patellar craniocaudal thickness (P) measured on computed tomography, to assess trochlear sulcus depth in Pugs, French Bulldogs and English Bulldogs without clinical patellar luxation. The effect of breed on T/P was assessed using one-way linear regression models.

Results The mean T/P was affected by breed (p < 0.001). There was significant difference between Pugs (0.45) and French Bulldogs (0.38) and between Pugs and English Bulldogs (0.4). There was no significant difference between Pugs and previously published data for non-brachycephalic and mixed breed dogs (0.46) (p = 0.39). Mean T/P was significantly reduced in the brachycephalic dog breeds combined compared with the previously published data (p < 0.001).

Conclusion The trochlear sulcus varies by breed and was more shallow in French and English Bulldogs than Pugs, hence a shallow sulcus may be a breed-driven characteristic. The three breeds assessed are at risk of patellar luxation but sulcus depth did not directly correlate with previously published risk factors—the contribution of sulcus depth to the aetiopathogenesis of patellar luxation remains unclear. Trochlear recession to achieve patellar coverage of 50% may be excessive considering maximal breed normal depth.

目的 本研究的目的是确定三种常见的有髌骨内侧脱位风险的短头动物的滑车沟深度。

研究设计 回顾性盲法临床研究使用先前验证的最大滑车沟深度 (T) 和最大髌骨颅尾厚度 (P) 的比率 (T/P) 在计算机断层扫描上测量，以评估哈巴狗、法国斗牛犬和英国斗牛犬的滑车沟深度无临床髌骨脱位。使用单向线性​​回归模型评估品种对 T/P 的影响。

结果 平均 T/P 受品种影响 ( p  < 0.001)。哈巴狗 (0.45) 和法国斗牛犬 (0.38) 以及哈巴狗和英国斗牛犬 (0.4) 之间存在显着差异。哈巴狗与之前公布的非短头犬和混合品种犬的数据之间没有显着差异 (0.46) ( p  = 0.39)。与先前公布的数据相比，短头犬品种的平均 T/P 显着降低（p  < 0.001）。

结论 滑车沟因品种而异，法国和英国斗牛犬的滑车沟比哈巴狗更浅，因此浅沟可能是品种驱动的特征。评估的三个品种有髌骨脱位的风险，但沟深度与先前公布的风险因素没有直接关联——沟深度对髌骨脱位发病机制的贡献尚不清楚。考虑到最大品种正常深度，滑车后退达到 50% 的髌骨覆盖率可能是过度的。