co-authors as well, we have no disclosures related to this study. So in recent years, biological treatments such as platelet-rich plasma have shown promise as effective treatment options for early osteoarthritis in multiple joints outside of the hip. In addition, hyaluronic acid is a glycosaminoglycan that is normally present in our synovial fluid, which acts as a fluid shock absorber that protects our intracellular collagen network from mechanical stress. Preliminary studies of PRP versus hyaluronic acid for hip osteoarthritis have shown conflicting results with no analysis of survivorship. The purpose of this study was to compare the efficacy of intra-articular injections of hyaluronic acid and PRP in patients with early hip OA. This was a prospective double-blind, randomized controlled trial on patients with early hip OA defined by a Kellgren-Lawrence grade of one through three. All patients completed baseline WOMAX scores, and patients who underwent previous hip surgery or an intra-articular corticosteroid injection within the previous six months were excluded. All patients were randomized to treatment with either PRP or HA using a computer-generated randomization table. Patients in either group underwent a total of three injections at one-week intervals, and prior to all injections, patients in both groups had their blood drawn in order to maintain the double-blind methodology. Patients randomized to the hyaluronic acid group were treated with SUPARTS, and patients randomized to the PRP group had their PRP obtained using a commercial kit. All patients were instructed to avoid blood thinners, including aspirin and NSAIDs, from two days before to five days after all injections, and patient-reported outcomes in hip range of motion were assessed at baseline, and at six weeks and three and six months following the initial injection by an examiner who was blinded to the applied treatment. Overall, 30 patients in 32 HIPs were enrolled between 2013 and 2018, with a mean age of 53 years in both groups, and of note, there was no significant difference in the proportion of baseline Kellgren-Lawrence grades between the two groups. In terms of survivorship, significantly more patients who received hyaluronic acid injections withdrew to undergo either a total hip arthroplasty or hip resurfacing procedure compared to patients in the PRP group. 50% versus only 11%, and this was statistically significant. In terms of the WOMAC scores, the PRP group demonstrated significant improvements from baseline to six weeks in terms of the WOMAC joint function and overall scores. In addition, this group showed significant improvement from baseline to six months in terms of the WOMAC joint score. And overall, the PRP group demonstrated greater improvement in most of these subscores, but this wasn't always statistically significant due to a relatively low sample size. And overall, the hyaluronic acid group showed no significant improvements in terms of any of these subscores at any time point. Finally, looking at range of motion in terms of hip internal rotation, the PRP group demonstrated significantly greater improvement from baseline to six months compared to the hyaluronic acid group, and the HA group actually showed a decline in this outcome from baseline to six months. So in conclusion, in this double-blind, randomized controlled trial, patients treated with PRP underwent total hip arthroplasty or hip resurfacing at a significantly lower frequency compared to those treated with hyaluronic acid, and patients treated with PRP were found to have more significant and continuous improvements in WOMAC scores and hip internal rotation range of motion. We believe that further study is needed to determine the efficacy of intra-articular hyaluronic acid injections in patients with early hip OA. Thank you.

platelet-rich plasma

hyaluronic acid

intra-articular injections

hip osteoarthritis

efficacy