Extracorporeal shock wave therapy promotes cell proliferation and collagen synthesis of primary cultured human tenocytes

The aim of this study was to investigate whether the effects of extracorporeal shock wave therapy (ESWT) could affect the behavior of primary cultured human tenocytes over a 12-day period. In this controlled laboratory study, primary human tenocytes were established from semitendinosus tendons collected from 3 patients undergoing arthroscopic anterior cruciate ligament (ACL) reconstruction. Cell viability, overall cell morphology, cell proliferation, and collagen synthesis following ESWT have been evaluated. ESWT significantly interferes with the overall cell morphology, by impairing dedifferentiation of the cells. Furthermore, a shock wave-mediated growth-promoting effect was measured by the MTT (tetrazolium) colorimetric assay and by the proliferation marker Ki67. Lastly, a significant increase in collagen (mainly type I) synthesis by ESWT-tenocytes compared with control cells was found. Shock wave treatment promoted cell growth and collagen synthesis of primary cultured human tenocytes. The clinical benefits of ESWT may be ascribed to an increased efficiency of tendon repair after injury.