PRP outperformed cortisone and NSAIDs in late-stage knee arthritis trial

A randomized trial in 90 patients already waiting for knee replacement found that platelet-rich plasma delivered better pain, function, opioid-use and biomarker results than cortisone or oral anti-inflammatories over six months. The findings matter because the study focused on severe “bone-on-bone” osteoarthritis, a group often left with surgery as the only option.

Why it matters: - The trial tested platelet-rich plasma in patients with advanced knee osteoarthritis who were already on the waiting list for total knee replacement. - The results suggest PRP may serve as a bridge therapy for severe arthritis, with benefits that went beyond symptom scores to include blood markers linked to inflammation and cartilage breakdown. - The study challenges the common assumption that late-stage “bone-on-bone” knees have no non-surgical options left.

What happened: - A randomized controlled trial accepted for publication in the Journal of Orthopedic Surgery and Research compared two PRP injections with corticosteroid injection and oral anti-inflammatory treatment. - Investigators enrolled 90 patients ages 40 to 80 in Košice, Slovakia, between September 2024 and June 2025. - All participants had Kellgren-Lawrence grade 3 or 4 knee osteoarthritis and were already awaiting knee replacement. - Patients were assigned to two intra-articular injections of non-activated autologous PRP one week apart, a single betamethasone injection, or oral aceclofenac. - Eighty-two patients completed six-month follow-up.

The details: - Pain scores in the PRP group fell from 6.2 at baseline to 3.3 at three months and 3.7 at six months. - Pain scores in the corticosteroid group moved from 6.3 to 5.8, while the NSAID group also went from 6.3 to 5.8. - Total WOMAC scores improved only in the PRP group, dropping from 49.0 to 28.1 at three months and 32.5 at six months. - The corticosteroid group was essentially unchanged at 45.6, while the NSAID group worsened from 48.8 to 57.9 at six months. - Rescue opioid use, measured in morphine milligram equivalents, was lowest in the PRP group and was significantly lower than corticosteroid at three and six months, and lower than NSAID at three months. - No patients in the PRP arm withdrew. - Two corticosteroid patients and four NSAID patients left after three months because pain remained uncontrolled and they moved to earlier surgery. - Two additional NSAID patients were withdrawn after worsening ischemic heart disease. - PRP patients showed lower levels of COMP, MMP-3, IL-6, IL-18 and TNF-α than the corticosteroid group at three months. - PRP patients also showed higher levels of sTREM2, sRAGE and TGF-β1, while CGRP was lower than both control groups. - Reductions in COMP, IL-6 and IL-18 remained present at six months. - Three PRP patients had transient knee pain and swelling that resolved within one day. - No other adverse events were recorded in the PRP arm. - The authors concluded PRP is supported as a safe bridge therapy before arthroplasty. - The study did not assess structural imaging or cartilage regrowth.

Between the lines: - The biomarker shifts matter because they hint at biological effects beyond short-term pain relief, but the biomarker work was exploratory and not adjusted for multiple comparisons. - The trial was single-center and not blinded, and the treatment arms differed in route, dosing frequency and treatment intensity, which limits direct comparison. - The PRP product was not quantitatively characterized in the study. - The NSAID arm had substantial dropout because of poor pain control and adverse effects, which weakens the control comparison. - The findings add to a broader argument that advanced knee pain may involve the subchondral bone and inflammatory biology, not just cartilage loss. - A separate November 2025 trial in the Journal of Clinical Medicine found that adding intraosseous infiltration to growth-factor therapy improved outcomes in severe knee osteoarthritis, though that study also did not measure structural imaging.

What's next: - The study adds momentum for larger, blinded trials that compare biologic injections more directly in end-stage knee arthritis. - Further research will need imaging endpoints, standardized PRP characterization and surgery-avoidance data to show whether biologic treatment changes the long-term course. - Regen.MD says patients seeking treatment begin with a Clinical Evaluation that includes imaging review, ultrasound examination and metabolic laboratory work, with a $400 non-refundable fee through the clinical application. - Regen.MD also says its orthobiologics program includes image-guided intra-articular and subchondral PRP, BMAC, adipose-derived Lipogems grafts and intradiscal orthobiologics.

The bottom line: - In severe knee osteoarthritis, PRP beat cortisone and oral anti-inflammatories on pain, function, opioid use and several inflammatory biomarkers, but the trial does not show cartilage regrowth or prove that surgery can be avoided long term.