Abstract
Background Osteoarthritis (OA) is a degenerative disease commonly affecting the knee joints. It affects patients socially, psychologically and economically and rates of the disease have been increasing due to obesity and old age. Regardless of choosing a medically conservative approach, it is a challenge in the long term to provide OA patients efficient treatment with minimal side effects and long-term efficiency. Platelet-rich plasma (PRP) is a convenient, low-cost and affordable treatment technique used in treating knee OA with encouraging efficient and safe outcomes. In this study we will investigate the effect of PRP on knee OA. Methods This is a prospective cohort study involving 252 patients with different OA grades. The Kellgren and Lawrence (K&L) system was used in classifying the affected knee by degenerative cartilage lesions as well as early and severe OA. All patients with a diagnosis of knee OA were screened in every visit before the injection, the pain was assessed by the 0-10 Numeric Rating Scale (NRS), and knee range of motion including flexion and extension was assessed by goniometer. Follow-up appointments were done on three-month intervals for a total of three visits for evaluation. Injection of PRP was given to all the patients with a maximum of four injections. The results were evaluated statistically according to the total number of follow-up visits. Results In grade II patients, the pain improved with the visits and the maximum improvement in flexion degree was noticed in patients who came for a total of three follow-up visits. In grade III patients, the most improvement in pain was in patients who came for three follow-up visits, while the most improvement in flexion degree was in patients who came for a total of two follow-up visits. Patients with grade IV who came for three follow-up visits showed the most improvement in pain and degree of flexion. Conclusions Intra-articular injections gave significant pain and flexion improvement in grades II, III and IV in OA patients, especially with multiple injection in the short-term follow-up. As a result, recommendation of repeated multiple injections up to four times is efficient in providing long time relief in knee OA.