In a randomized, controlled trial , Level of Evidence 1(best), Patel, et al, (reference 1), divided patients into 3 groups:
- Group A-52 Osteoarthritis (OA) knees, single Platelet-Rich Plasma (PRP) injection
- Group B: 50 OA knees, 2 injections
- Group C- 46 OA knees, single saline placebo (control) injection.
All PRP was White Blood Cell (WBC)-poor PLT count 300% of whole blood values. Results: All WOMAC (knee pain rating scale) parameters improved significantly in Group A, B within 2-3 weeks, lasting to 6 months follow-up. Lesser grades of arthritis did better, and 22% of Group A patients had mild complications (nausea, dizziness), while 44% of Group B had mild complications.
Conclusion: Both groups treated with a leukocyte-poor Platelet-Rich Plasma (LR-PRP) had significantly superior results compared to control (placebo) patients. Results declined after 6 months. Single dose as effective as two injections.
Patel,et al,Treatment with platelet-rich plasma is more effective than placebo for knee osteoarthritis: A prospective, randomized, double-blind trial. Am J Sports Med 2013; 41 (2): 356-364.