Spinal Arachnoid Diverticula

Spinal arachnoid diverticula (previously called spinal arachnoid cyst) are dilations of the cavity in the normal brain (subarachnoid space), which can lead to a progressive, compressive disease of the spinal cord (myelopathy). Although spinal arachnoid diverticula can occur over the entire length of the vertebral column, cervical lesions are seen most commonly in large breed dogs while lesions in the lower regions of the spine are more common in small breed dogs. Rottweilers, Pug dogs and French Bulldogs might have a predisposition for the disease development. In a large percentage of these dogs, a concurrent spinal disorder, which might predispose to SAD formation, is often diagnosed.

Clinical signs can vary from a mild‐to‐severe poor movement coordination (ataxia) with fecal, urinary incontinence, or both. The most characteristic clinical sign is a moderate ataxia without any signs of discomfort. The age of onset of the disease is between 3 months and 13 years. Male dogs are most commonly affected. A possible hereditary cause is suspected as well as congenital causes, biomechanical factors, and concurrent or previous spinal disorders, for example, intervertebral disk extrusion and protrusion or inflammatory disorders, such as meningo‐myelitis.


  1. Signalment, Clinical Presentation, and Diagnostic Findings in 122 Dogs with Spinal Arachnoid Diverticula. D.A. Mauler et al.