Congenital anomalies affecting the spinal column are frequently observed in certain dog breeds. One such condition occurs at the junction between the lower back and the sacrum, where vertebrae exhibit mixed structural characteristics. This retrospective study analysed imaging records of Rhodesian Ridgebacks collected over 28 years, selecting only those that met strict positioning standards for evaluation. A total of 2 012 cases were analysed using established classification methods, identifying three distinct structural variations: a typical junction, a bilaterally altered morphology, and an asymmetrical form affecting one side. The prevalence of these variations was 7.4%, with symmetrical alterations found in 5% of cases and asymmetrical alterations in 2.4%. Statistical analysis did not reveal a significant association between these anatomical variations and canine hip dysplasia (CHD) (P = 0.170 0). These findings support previous research indicating that there is no direct link between these structural variations and joint disorders in this breed. The study represents the most extensive investigation of its kind in this canine population, highlighting that such vertebral variations are frequently observed in routine radiographic screenings, but despite decades of research, consistent clinical correlations remain elusive – underscoring the need for further systematic investigation.
Slunsky et al. (2025) studied this question.