Does Long-Term Compressive Loading on the Intervertebral Disc Cause Degeneration?

摘要: STUDY DESIGN Coil springs were stretched and attached to produce a compressive force across the lumbar intervertebral discs of dogs for up 53 weeks. OBJECTIVE To test hypothesis that forces applied disc long period time cause degeneration in vivo dog model. SUMMARY OF BACKGROUND DATA It is commonly held belief high disc, joints general, play role causing degeneration. METHODS (L3/L4) 12 dogs. After year, killed, their spines removed radiographed. The L3/L4 controls (T13/L1 L4/L5) excised examined visible signs then assessed using immunohistochemical analysis enzyme-linked immunosorbent assay. Disc chondrocytes also assayed apoptosis. RESULTS No obvious had been under compression year could be observed. There was no bulging, anular fissures, or space narrowing. Some changes observed at microscopic level, although thickening endplate apparent. assay provided significant data all three regions (nucleus, inner anulus, outer anulus). When comparing compressed with either control L4/L5), disc: 1) nucleus contained less proteoglycan more collagen I II; 2) anulus I; 3) I. II differences not significant. CONCLUSION Compression does any form. numerical changes, however, amounts nucleus, anulus. present results add credence causative