Prevalence of lumbosacral transitional vertebrae in dogs in Berlin

Lumbosacral transitional vertebrae (LTV) are abnormally formed vertebrae of congenital origin. Dogs with LTV are predisposed to premature degeneration of the lumbosacral spine and hip dysplasia due to a weakened sacroiliac attachment. Moreover, LTV has been discussed as a cause of cauda equina syndrome. To date, LTV remain poorly understood and a diagnostic standard is yet to be established. This study examines prevalence, types and breed predispositions for LTV in the canine population in Berlin. The diagnostic value of laterolateral radiographs of the lumbosacral region, in addition to ventrodorsal radiographs, was also evaluated. The prevalence of LTV was assessed by reviewing ventrodorsal pelvic radiographs of 1030 dogs. LTV were detected in 95 (9.2%) dogs. The prevalence was higher in Pugs (63.6%) and Jack Russel Terriers (27.6%) than in the other breeds. The most common type of LTV was type II (37.9%), showing separation of the first sacral segment from the sacrum, the presence of a rudimentary intervertebral space between the first sacral segment and the rest of the sacrum, and symmetrically formed transverse processes. Laterolateral radiographs were available for 66 of 95 dogs with LTV and provided evidence of a rudimentary intervertebral disc space between the first and second sacral vertebrae in all cases of LTV type II and III (100%). The results of this study contribute to a better understanding of the condition. Furthermore, they demonstrate that laterolateral radiographs are a valuable addition to standard ventrodorsal radiographs and should be included in routine LTV screening protocols to provide a complete evaluation.