Mechanical stress in vitro induces increased expression of MMPs 2 and 9 in excised Dupuytren's disease tissue.

We have previously shown that the ability to mechanically extend Dupuytren's contractures in vivo by the Continuous Elongation Technique before surgery resulted in increased metalloproteinase activity. However, under these conditions it was not possible to show whether the response was proportional to the mechanical stimulus or was inflammatory cell mediated. Using an in vitro system of controlled extensions in which inflammatory involvement is absent, we have now shown that there is a clear correlation between the load applied to the tissue and the release of matrix metalloproteinase-2. The subsequent degradation of the collagen results in a loss of mechanical strength reported in the preceding paper.