Molecular changes after shockwave therapy in osteoarthritic knee in rats

Abstract

This study investigated the molecular changes of DKK-1, MMP13, Wnt-5a and \(\upbeta \)-catenin after extracorporeal shockwave therapy (ESWT) in anterior cruciate ligament transected (ACLT) osteoarthritic (OA) knee in rats. 27 male Spraque-Dawley rats were divided into three groups. Group I was the control one and received sham knee arthrotomy but no ACLT or ESWT. Group II underwent ACLT, but no ESWT. Group III underwent ACLT and received ESWT. The animals were killed at 12 weeks, and the harvested knee specimens were subjected to histopathological examination and immunohistochemical analysis. Radiographs of the knees were obtained at 0 and 12 weeks. At 12 weeks, radiographs of group II showed more arthritic changes with formation of osteochondral fragments, whereas very subtle arthritis was noted in groups I and III. In histopathological examination, group II showed a significant increase of Mankin score and a decrease of subchondral bone as compared to groups I and III. Group III showed a significant decrease of Mankin score and an increase of subchondral bone, with the data comparable to group I. In immunohistochemical analysis, group II showed significant increases of DKK-1 and MMP13 and decreases of Wnt-5a and \(\upbeta \)-catenin in articular cartilage and subchondral bone as compared to groups I and III. Group III showed significant decreases of DKK-1 and MMP13 and increases of Wnt-5a and \(\upbeta \)-catenin, with the data comparable to group I. In conclusion, the application of ESWT causes molecular changes that are consistent with the improvement in subchondral bone remodeling and chondroprotective effect in ACLT OA knees in rats.