Summary
The medical records of 156 dogs with degenerative lumbosacral stenosis (DLS) that
underwent decompressive surgery were reviewed for signalment, history, clinical signs,
imaging and surgical findings. The German Shepherd Dog (GSD) was most commonly affected
(40/156, 25.6%). Pelvic limb lameness, caudal lumbar pain and pain evoked by lumbosacral
pressure were the most frequent clinical findings. Radiography showed lumbosacral
step formation in 78.8% (93/118) of the dogs which was associated with elongation
of the sacral lamina in 18.6% (22/118). Compression of the cauda equina was diagnosed
by imaging (epidurography, CT, or MRI) in 94.2% (147/156) of the dogs. Loss of the
bright nucleus pulposus signal of the L7-S1 disc was found on T2-weighted MR images
in 73.5% (25/34) of the dogs. The facet joint angle at L7-S1 was significantly smaller,
and the tropism greater in GSD than in the other dog breeds. The smaller facet joint
angle and higher incidence of tropism seen in the GSD may predispose this breed to
DLS. Epidurography, CT, and MRI allow adequate visualization of cauda equina compression.
During surgery, disc protrusion was found in 70.5% (110/156) of the dogs. Overall
improvement after surgery was recorded in the medical records in 79.0% (83/105) of
the dogs. Of the 38 owners that responded to questionnaires up to five years after
surgery, 29 (76%) perceived an improvement.
Keywords
Degenerative lumbosacral stenosis - cauda equina - dog