Molecular changes after shockwave therapy in osteoarthritic knee in rats

This study investigated the molecular changes of DKK-1, MMP13, Wnt-5a and β-catenin after extracorporeal shock wave therapy (ESWT) in anterior cruciateligament 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 animalswerekilledat12weeks,andtheharvestedkneespec- imens were subjected to histo pathological examination and immune histo chemical 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 sub chondral 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 β-catenin in articular cartilage and subchondral bone as compared to groups I and III. Group III showed sig-nificant decreases of DKK-1 and MMP13 and increases of Wnt-5a and β-catenin, with the data comparable to group I. In conclusion, the application of ESWT causes molecular changes that are consistent with the improvement in sub-chondral bone remodeling and chondroprotective effect in ACLT OA knees in rats.