Verification of the effectiveness of combined platelet-rich plasma therapy and exercise therapy for patients with knee osteoarthritis up to one year post-treatment

Abstract Background Platelet-rich plasma (PRP) therapy is a promising treatment modality for knee osteoarthritis (OA). However, exercise therapy and activity of daily living (ADL) guidance are also recommended as core treatments in the Osteoarthritis Research Society International (OARSI) guidelines. However, there is limited research on the efficacy of combined PRP and exercise therapy. This study aimed to verify the effectiveness of this combined treatment. Methods The participants were patients diagnosed with knee OA and treated between January 2021 and December 2022. They were divided into three groups: 1) PRP + exercise therapy (PE group), 2) PRP therapy only (P group), and 3) exercise therapy only (E group). Outcomes were measured using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and conducted before, 1 month, 3 months, and 1 year after treatment. Statistical analysis was performed using a one-way analysis of variance for within-group comparisons according to the time of each score. For those that showed a difference, the Bonferroni multiple comparison method was used to validate the results (p < 0.05). The treatment response rate was determined using the Outcome Measures in Rheumatology (OMERACT)-OARSI Responder criteria. Results There were no differences in pre-treatment KOOS between the three groups. In the PE group, pain, symptoms, and ADL improved after 1 month and continued to improve until 1 year. The P group showed improvement in pain after 1 month, but no significant changes were observed in the other items. In contrast, the E group showed improvement in each item from 3 months onwards, with all items remaining unchanged at 1 year. The PE group had a higher response rate than the other groups, with 50.0% at 1 month, 56.3% at 3 months, and 68.8% at 1 year, according to the responder criteria. Conclusions The combined treatment of PRP and exercise therapy demonstrated the synergistic advantages of both and proved to be most effective up to 1 year after treatment.