Aims. Platelet-rich plasma (PRP) intra-articular injections may provide a simple and minimally invasive treatment for early-stage knee osteoarthritis (OA). This has led to an increase in its adoption as a treatment for knee OA, although there is uncertainty about its efficacy and benefit. We hypothesized that patients with early-stage symptomatic knee OA who receive multiple PRP injections will have better clinical outcomes than those receiving single PRP or placebo injections. Methods. A double-blinded, randomized placebo-controlled trial was performed with three groups receiving either placebo injections (Normal Saline), one PRP injection followed by two placebo injections, or three PRP injections. Each injection was given one week apart. Outcomes were prospectively collected prior to intervention and then at six weeks, three months, six months, and 12 months post-intervention. Primary outcome measures were Knee Injury and Osteoarthritis Outcome Score (KOOS) and EuroQol five-dimension five-level index (EQ-5D-5L). Secondary outcomes included visual analogue scale for pain and patient subjective assessment of the injections. Results. A total of 102 patients were recruited. The follow-up period was 12 months, at intervals of six weeks, 12 weeks, six months, and 12 months. KOOS-Total significantly improved in all groups at these time intervals compared to pre-injection. There was an improvement in EQ-5D-5L index scores in saline and single injection groups, but not in the multiple injection group. Comparison of treatment groups showed no additional beneficial effect of single or multiple PRP injections above that displayed in the saline injection group. Subjective patient satisfaction and recommendation of treatment received demonstrated a similar pattern in all the groups. There was no indication of superiority of either single or multiple PRP injections compared to saline injections. Conclusion. There is no evidence that single or multiple PRP had any additional beneficial effect compared to saline injection up to 12 months, follow-up after treatment of early stage symptomatic OA of the knee. Cite this article: Bone Joint J 2022;104-B(6):663–671

Introduction. The use of stem cell and platelet-rich plasma (PRP) injections for knee osteoarthritis (OA) is extremely controversial and at best experimental. These treatments are being given to patients across the nation for “cash only payments”. Our objectives were (1) to determine the proportion of board certified orthopedic surgeons who offer stem cell or PRP treatment for knee OA, (2) how much the practices charge for those treatments and (3) if members of the knee society use these therapies. Methods. Board certified orthopedic surgeons’ offices in our county were identified by their AAOS active membership. Knee society membership roll was also utilized. Offices were contacted by telephone and presented with a hypothetical patient with end stage knee osteoarthritis searching for specific treatment (stem cells or PRP injections). T-test was used to compare the Dade county board certified orthopedists to knee society members. Results. A total of 186 board certified orthopedic surgeons’ offices were contacted. 17.6% of all contacted orthopedics offices offered PRP and 12.5% offered stem cell treatments. 61.2% of the offices were transparent on the pricing of PRP while 31.8% gave a price for stem cell therapy. The remaining practices stated that pricing would be “determined or discussed” during a scheduled visit. Mean cost for a PRP injection was $887 (SE 101; range: $350–$1700) and for a stem cell injection was $2800 (SE 852; range: $1000–$6000). Usage of these therapies amongst general AAOS members and Knee Society members was found to be significantly different for both PRP and stem cells (17% vs. 10%; p<0.001 and 26% vs. 13%; p<0.001, respectively). No practice had a “free” research protocol to study the treatments. Conclusions. Biological injectables as a treatment for knee OA has theoretical potential promise in the management of arthritis but continues to be at best investigational. Knee Society members demonstrated significantly more caution using these treatments