It has been reported that MMP-3 plays a central role in early matrix destruction, whereas it is down-regulated in the late stages of matrix destruction.21,22) Considering that the expression pattern of MMP-3 depends on the disease stage, it is not unexpected that the expression of MMP-3 was not significantly higher in the spinal stenosis ligamentum flavum samples with their elastin degradation, and fibrosis is thought to be a chronic or late-stage finding of spinal stenosis. Here, MMP3 is linked to spinal stenosis.