Comparative Analysis of the Effectiveness of Intraarticular Injection of Platelet-Rich Plasma versus Hyaluronic Acid for Knee Osteoarthritis: Results of an Open-Label Trial

Background: Platelet-rich plasma (PRP), an autologous source of growth factors, and hyaluronic acid (HA) are amongthe minimally invasive treatments for knee osteoarthritis (OA). This trial was designed to compare the effectiveness ofintra-articular injection of PRP with HA (as one of the standard treatments) on mild to moderate knee OA.Methods: In this phase I open-label clinical trial, ۱۰ patients underwent intra-articular PRP injection and ۱۰ othersreceived HA injection. At baseline (pre-injection) visit and ۱, ۳, ۶, and ۱۲ months post-injection, clinical assessmentswere performed using visual analogue scale (VAS) and Knee injury and Osteoarthritis Outcome Score (KOOS)questionnaire. Physical examinations of the knee, including crepitation and range of motion (ROM) were performed ateach visit. The follow-up responses were compared with the baseline visit.Results: The PRP treatment was ascertained to be safe and caused no adverse effects. Significant improvementsin the majority of KOOS subscales and VAS were found throughout the entire ۱۲-month follow-up, following the PRp injections. HA injection, however, caused only one month significant improvement in the majority of patient-reportedoutcomes. In the majority of visits, the extent of improvements in the scores of KOOS subscales, as well as the extentof reduction in VAS were significantly greater in PRP recipients, compared to HA recipients. The ROM in both groupsslightly increased after interventions. The frequency of coarse crepitation, which was detected in ۱۰۰% of the patientsin both groups at the baseline visit, decreased significantly to fine crepitation at the first follow-up visit in ۸۰% and ۴۰%of the PRP and HA recipients, respectively.Conclusion: Intra-articular injection of PRP or HA alleviates symptoms and pain and improves functionality and physicalexaminations in patients with knee OA. However, PRP therapy produces greater and longer-lasting improvements inmost of the outcome parameters compared to HA.Level of evidence: II

Keywords:

Comparative Study , Hyaluronic acid , Intra-Articular Injections , Knee Osteoarthritis , Platelet-rich plasma