ORIGINAL ARTICLE Clinical outcomes are associated with changes in ultrasonographic structural appearance after platelet-rich plasma treatment for knee osteoarthritis Hamada S. AHMAD, 1 Sherief E. FARRAG, 1 Amr E. OKASHA, 1 Aisha O. KADRY, 2 Tamer B. ATA, 3 Amir A. MONIR 4 and Ibrahim SHADY 5 1 Rheumatology and Rehabilitation Department, Mansoura Faculty of Medicine, Mansoura University, Mansoura, 2 Physical Medicine, Rheumatology, and Rehabilitation, Al Azhar Faculty of Medicine, Al Azhar University, Cairo, 3 Medical Microbiology and Immunology, 4 Diagnostic Radiology, and 5 Community Medicine Department, Mansoura Faculty of Medicine, Mansoura University, Mansoura, Egypt Abstract Background: Hyaluronic acid (HA) and platelet-rich plasma (PRP) are two treatment options used for knee osteoarthritis (KOA) but studies comparing the efficacy of the two yield conflicting results. In addition, the asso- ciation of clinical outcomes of PRP intra-articular injections with changes in the ultrasonography structural appearance of the knee has not been investigated. Aim: To compare the efficacy of PRP and HA intra-articular injections as mono-therapeutic options for primary KOA, and to determine whether the clinical outcomes are associated with changes in the ultrasonography struc- tural appearance. Subjects and methods: A randomized clinical trial was conducted on 89 patients with KOA. The patients were given either PRP (n = 45) or HA (n = 44) intra-articular injections. The patients received three injections in the knee, which was more symptomatic at baseline evaluation, with a 2-week interval between injections. The out- come measures included visual analog score – pain, International Knee Documentation Committee Score, and assessment of synovial hypertrophy, synovial vascularity and knee effusion using ultrasonography. Outcome measures were assessed at baseline and at 3 and 6 months post-injection. Results: While both PRP and HA injections resulted in the improvement of all outcome measures at 3 and 6 months follow up, they were significantly better in the PRP group than in the HA group. Conclusion: Intra-articular injection of PRP is an effective treatment that reduced pain and improved functional status in patients with KOA. The clinical outcomes of the intra-articular injections of PRP are associated with improved synovial hypertrophy and vascularity scores, and less effusion. Key words: clinical aspects osteoarthritis, clinical trials, drug treatment osteoarthritis. INTRODUCTION Osteoarthritis (OA) is the most common form of arthri- tis, especially among the elderly, and is a leading cause of chronic disability worldwide, mostly as a conse- quence of knee OA (KOA). 1 Millions of people affected by KOA suffer from chronic pain which affects their quality of life. 2 Among those older than 45 years, 16.7% have symptomatic KOA, 27.8% show radio- graphic evidence for KOA, and the remaining 87% have bilateral KOA. 3 Moreover, an increase in the prevalence of symptomatic KOA by 4.1% and 6% has been Correspondence: Dr Ibrahim Shady, Community Medicine Department, Mansoura Faculty of Medicine, Mansoura University, El Gomhouria St, Mansoura, Dakahlia Gover- norate 35516, Egypt. Email: ebrshady@outlook.com © 2018 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd International Journal of Rheumatic Diseases 2018; 21: 960–966