Effects of Platelet-Rich Plasma Injection in Knee Osteoarthritis Stages 1-4: A Retrospective Cohort Study.

Background and aim Knee osteoarthritis (OA) is a common degenerative joint disorder and a major cause of pain and disability. Platelet-rich plasma (PRP) injections have evolved as an option for the management of knee OA. However, there is a need for studies across different populations and geographic regions. The aim of this study was to assess the outcomes of PRP injections in different stages of knee OA in the Arab population of Kuwait. Methods Data were collected retrospectively. Outcome measures were the Verbal Numerical Rating Scale (VNRS) and the reduced Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). The paired t-test was applied to compare changes in outcomes at three- and six-month follow-up. Effect size was calculated using Cohen's d standardized mean difference. Results In all patients, there was a reduction (p < 0.001) in VNRS at three months (2.87 ± 2.33) and at six months (3.07 ± 2.3) compared with the pretreatment pain score. There was also a reduction (p < 0.001) in WOMAC score at three months (4.8 ± 5.08) and at six months (4.42 ± 5.21). No adverse effects were reported in patients during the study period. Conclusions Intra-articular PRP injections may be safe and effective for pain relief and functional improvement for up to six months in all stages of knee OA. To the best of our knowledge, this is the first such study in a large sample of Arab patients.