Canine Cauda Equina Syndrome Study Guide

Overview and Clinical Importance

Cauda equina syndrome (CES), also known as degenerative lumbosacral stenosis (DLSS) or lumbosacral disease, is a common neurologic disorder affecting the nerve roots of the cauda equina at the lumbosacral junction in dogs. This condition represents a significant category of spinal disease on the NAVLE, particularly due to its high prevalence in working and large-breed dogs.

The term cauda equina is Latin for "horse's tail" and refers to the bundle of nerve roots (L7, S1-S3, and Cd1-Cd5) that extend from the terminal spinal cord and traverse the lumbosacral vertebral canal. Compression of these nerve roots leads to the characteristic clinical signs of low back pain, pelvic limb dysfunction, and in severe cases, urinary and fecal incontinence.

Anatomy of the Lumbosacral Junction

Understanding the anatomy of the lumbosacral junction is essential for diagnosing and treating CES. The canine spine consists of 7 cervical, 13 thoracic, 7 lumbar, 3 fused sacral, and variable caudal vertebrae. The lumbosacral junction (L7-S1) is a critical transition zone where the mobile lumbar spine meets the relatively immobile sacrum and pelvis.