Transitional lumbosacral vertebrae in black Norwegian elkhound and Brittany dogs: Clinical findings and its association with degenerative lumbosacral stenosis.

Background: Lumbosacral transitional vertebra (LTV) is a congenital anomaly in dogs and have been proposed to be associated with cauda equina syndrome (CES) in German Shepherd dogs. This prospective study, including 32 dogs from two breeds, aims to investigate if LTV is associated with lower back pain in dogs. The study compared owners' assessment of their dogs' well-being and clinical evaluation with advanced diagnostic imaging to identify changes that might explain clinical findings.

Results: Dogs with LTV type 2 (57.0%) and with LTV type 3 (70.0%) exhibited mild lower back pain, which was significantly more frequent (P = 0.012) compared to dogs with LTV type 0 and LTV type 1. Advanced diagnostic imaging identified a plausible cause for this pain. Dogs diagnosed with LTV types 2 and 3 with lower back pain tended to be lighter (median 14.50 kg) and younger (median 4.10 years) than breeds typically reported for degenerative lumbosacral stenosis (DLSS). Based on the owners' assessment of their dogs, they considered them pain-free.

Conclusions: The study identified a correlation between LTV types 2 and 3 and lower back pain in these dog breeds. Advanced diagnostic imaging findings confirmed that dogs with these LTV types were more likely to exhibit pathological changes associated with DLSS.