Neurological and pathological effects of second lumbar spondylectomy and spinal column shortening in the dog.

The second lumbar vertebra was surgically removed from 10 dogs, and the shortened vertebral column was stabilized by internal fixation with two types of plastic plates. Shortening of the spinal column was usually not associated with detectable loss of function or neurological deficit. Histological lesions, however, included widely disseminated axonal degeneration, gliosis, and atrophy of spinal nerve roots in the surgical area. The spinal cord adapted to shortening of the vertebral column by becoming intrinsically shorter, rather than be being displaced within the spinal canal.