MRI Findings after Injection of Single and Double Centrifuged Platelet-Rich Plasma and Placebo (Normal Saline) in Patients with Knee Osteoarthritis: A Randomized Double-Blind Clinical Trial with Six-Month Follow-Up.

Abstract

This research aimed to compare the changes in knee MRI findings after the injection of platelet-rich plasma with those after the injection of a placebo (normal saline) in patients with knee osteoarthritis. This randomized clinical trial study was conducted on 63 patients with grade 2 and 3 knee osteoarthritis. Patients were randomly assigned to one of three injection groups: double-centrifuged PRP, single-centrifuged PRP, or placebo (normal saline). Patients were evaluated with MRI, VAS (visual analog scale), WOMAC (Western Ontario and McMaster Universities Arthritis Index), knee ROM (range of motion), and functional tests before and six months after the intervention. The investigated MRI characteristics included cartilage thickness of the medial tibia and patella, WORMS score of osteophyte and subchondral cyst, as well as severity of subchondral sclerosis. In the comparison between the three groups six months after the intervention, the VAS, ROM, functional tests, WOMAC scores, sclerosis severity, and the thickness of the medial tibial and patellar cartilage in the two groups, single centrifuged and double centrifuged, were significantly better than the placebo group. However, the mean overall WORMS score for osteophyte (p = 0.480) and subarticular cyst (p = 0.559) was not significant between the groups, and the PRP groups did not show a significant difference in reducing osteophyte and subarticular cysts compared to the placebo group. Compared to the control group, PRP was effective in improving pain, range of motion (ROM), functional performance, WOMAC scores, articular cartilage thickness, and the severity of sclerosis. No significant difference was observed between the two groups of PRP in improving these variables.