A Prospective, Randomized, Controlled Trial Comparing Clinical Outcomes of Intraarticular Platelet Plasma Concentrate and Growth Factors versus Corticosteroid Injections in the Treatment of Knee Osteoarthritis

Abstract

OBJECTIVES: To compare and evaluate the efficacy of intraarticular platelet-rich growth factor (PRGF) versus intraarticular steroid injections.

MATERIAL AND METHODS: A prospective, blinded, randomized controlled trial was conducted by enrolling 650 patients with knee osteoarthritis (OA) who did not respond to the combination of oral medication and physiotherapy. After computer-based randomization and exclusion, the number of patients in our study was 557. Patients were divided into 2 groups. Group 1 (310 patients) received intraarticular PRGF injection and group 2 (247 patients) received intraarticular injection of 40-mg triamcinolone solution. The post-trial follow-up period ranged from 12 to 18.5 months. The primary endpoints were the International Knee Documentation Committee (IKDC) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores and the secondary endpoints were the Visual Analog Scale (VAS) pain scores.

RESULT: The IKDC scores were measured at baseline, 2-, 4-, 6-, and 12-month follow-up after the injection. The IKDC scores of group 1 (PRGF treatment) were 39.48 ± 7.94, 48.47 ± 8.49, 51.04 ± 8.26, 51.54 ± 8.07, and 52.14 ± 9.86, and the IKDC scores of group 2 (steroid treatment) were 38.30 ± 7.26, 45.64 ± 9.45, 45.60 ± 10.24, 45.79 ± 9.96, and 43.14 ± 11.63, respectively. WOMAC scores were collected at the same period. The WOMAC scores of group 1 (PRGF treatment) were 56.91 ± 14.89, 42.54 ± 15.64, 38.13 ± 14.95, 36.41 ± 15.23, and 36.28 ± 17.86 and, for group 2 (steroid treatment), the scores were 56.73 ± 11.69, 45.22 ± 17.00, 46.37 ± 17.52, 46.47 ± 17.47, and 50.84 ± 20.29, respectively. Patients in group 1 and 2 both showed improvement after the treatment. The data showed significant statistical difference (p < 0.01) in almost all of the scoring, in favor of the PRGF injection, except no significance at the first 2 months (WOMAC, p = 0.053). The secondary outcome revealed a similar trend with significant statistical difference (p < 0.01) as the primary outcome did. PRGF was collected according to our novel Plasma Platelet Concentrate and Growth Factors (PP&GF) protocol. The average platelet concentration prepared by PP&GF protocol was 6 times (3-8.69) higher than the normal platelet concentration. There was no knee infection at the end of the follow up.

CONCLUSION: PRGF and intraarticular steroid injection result in good outcomes, however in terms of functional scoring (WOMAC and IKDC), PRGF treatment demonstrated significantly better clinical outcomes at 6- to 12-month follow-up. PRGF treatment can become an effective alternative treatment in knee OA. However, optimal preparation techniques are essential for improved clinical outcomes, and further investigation with long-term follow-up is recommended.