The effects of extracorporeal shockwave therapy on matrix metalloprotease activity in tendinopathy (1046.8)

Abstract

INTRODUCTION Extracorporeal shockwave therapy (ESWT) is an effective, non‐invasive treatment for degenerative tendinopathies, however, the biological mechanisms underpinning its therapeutic effects are largely unknown.METHODS The local tissue response of matrix metalloproteinase (MMP) ‐2 and ‐9 (gelatinases involved in extracellular matrix remodelling) to ESWT was examined in 18 healthy (18 Achilles) and 10 degenerative (4 Achilles, 6 patellar) tendons using microdialysis. Dialysate samples were collected from the peritendinous space before and after a single ESWT session. Analysis of MMP‐2 and ‐9 activities were completed using gelatin zymography.RESULTS Active MMP‐9 increased ~350% after ESWT, whereas pro‐MMP‐9 was not detected in our samples. There was a ~200% increase in a heavy MMP‐2 complex (~135 kDa; likely an MMP‐2 dimer) after ESWT when compared to baseline, however, levels of pro‐ and active MMP‐2 monomers did not change significantly. There were no response differences between healthy and degenerative tendons.CONCLUSION These findings provide evidence of the biological mechanisms underpinning ESWT in humans in vivo. Our findings are consistent with studies examining MMP activity after exercise and suggest that the mechanical stimulus provided by ESWT might initiate tendon remodeling in tendinopathy by promoting the catabolic processes required to remove damaged matrix constituents.Grant Funding Source: Engineering and Physical Sciences Reserach Council Knowledge Transfer Partnership