The effect of spinal fusion on the collagen and proteoglycans of the canine intervertebral disc

The effects on disc composition of 16 months of lumbar spinal arthrodesis in the greyhound (a nonchondrodystrophoid breed) have been investigated using age-matched controls. The guanidinium chloride-extractable proteoglycans of the disc's nucleus pulposus and annulus fibrosus were compared using equilibrium density gradient ultracentrifugation under associative conditions. No differences in proteoglycan sedimentation behavior were detected between discs from experimental or control animals. Analysis of individual discs for collagen, total nitrogen, noncollagenous protein, uronic acid, or total hexosamine content also failed to demonstrate statistically significant differences between the experimental and control groups.