Degenerative Myelopathy in the Aging German Shepherd Dog: Clinical and Pathologic Findings

SUMMARY Twenty-two dogs with progressive ataxic spastic paraparesis, 20 of which were German Shepherd Dogs, were examined. There was no sex predominance. Mean age of onset was 9.6 years; clinical signs progressed over a 1- to 3-month period prior to elective termination. Each of 7 dogs necropsied had diffuse degeneration of spinal cord myelin and axons in all funiculi, with subsequent astrocytosis and astrogliosis. The degenerative changes, which were most extensive in the midthoracic region, were not associated with intervertebral disk herniation, spondylosis deformans, or osseous metaplasia of the dura mater. The condition was regarded as primary spinal cord degeneration of unknown cause.