Effects of platelet-rich plasma on the clinical outcomes and cartilage thickness in patients with knee osteoarthritis

BACKGROUND: The interest in biological treatments that have the potential to modify cartilage biology has gradually increased in recent years. OBJECTIVE: The aim of our study was to investigate the effects of intra-articular platelet-rich plasma (IA-PRP) injections on the femoral cartilage thickness, pain, functional status, and quality of life of patients with knee osteoarthritis. METHODS: A total of 71 patients (109 knees) with knee osteoarthritis who were administered IA-PRP injections twice with two-week intervals were included in this study. The resting and activity pain values measured using a Visual Analogue Scale (VAS), the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores, the Lequesne index scores, and the quality of life scores measured using Short Form-36 (SF-36) were recorded before treatment and at 1 month, 3 months, and 6 months after treatment. The femoral cartilage thickness was measured via ultrasonography before treatment, and at 3-month and 6-month follow ups. Obtained results were analyzed by the Wilcoxon signed rank test. RESULTS: The mean age of the patients was 47.4 +/- 10.4 years old. The resting and activity pain scores were significantly decreased at 1-month, 3-month and 6-month follow ups when compared to the pre-injection values (p < 0.05). Significant reductions were found in the Lequesne index and WOMAC pain, stiffness, and function scores at 1, 3, and 6 months (p < 0.05), while a significant increase was detected in the third month scores when compared to the first month. Significant improvements were determined in the physical functioning, physical role, pain, general health, and emotional role sub-scores during the 6month period (p < 0.05). However, there was no significant difference with regard to the cartilage thickness at the follow ups (p > 0.05). CONCLUSIONS: The results of our study indicated that the IA-PRP injections improved the pain, stiffness, physical functioning, and quality of life of knee osteoarthritis patients; however, they did not seem to affect the cartilage thickness during the 6-month follow up period.