Editor’s Spotlight/Take 5: Is Platelet-rich Plasma Effective in Treating Achilles Tendinopathy? A Meta-analysis of Randomized Clinical Trials
Year: 2025
Type: review
Abstract: Some have said, tongue in cheek, that celebrity endorsements represent “Level VI evidence,” and on the subject of platelet-rich plasma (PRP), even our Academy offers patients an implied celebrity endorsement in the second sentence of its OrthoInfo page on the topic: “Many famous athletes—golfer Tiger Woods and tennis star Rafael Nadal among them—have received PRP for various problems, such as sprained knees and chronic tendon injuries” [1]. Later, that same OrthoInfo page states that “PRP does appear to be effective in the treatment of certain chronic tendon injuries,” before concluding that “even though the success of PRP therapy is still questionable, the risks associated with it are minimal.” Another patient page about Achilles tendinopathy specifically says that “several studies on PRP injections have shown improvements in pain. However, more information is needed to determine how effective PRP truly is for this condition” [5], leaving the unmistakable impression that PRP is, in fact, effective, at least to some degree. Unfortunately, despite anecdotes from Tiger and Rafa, the best available evidence suggests otherwise: PRP is not effective for this indication. Using—and charging for—an ineffective treatment isn't appropriate, even if the risk is “minimal.” We should look for other options. This finding gets underscored in this issue of Clinical Orthopaedics and Related Research® by an updated, high-quality meta-analysis of six randomized clinical trials [2], which we are proud to spotlight here. The authors, who were led by Durval Campos Kraychete PhD, found no benefits to this expensive treatment in terms of function or pain at 3, 6, or 12 months. Their findings were robust in the face of sensitivity analyses. This study extends on what two earlier review articles published here had shared [9, 14], and can best be summarized as follows: Until or unless new, large, high-quality RCTs upend what we think we know, PRP is no more effective than placebo for treating Achilles tendinopathy and should not be used for this indication. The authors of this month's Editor's Spotlight paper [2] (and perhaps the journal in which they published their work) can expect a backlash, since PRP is big business. The market for PRP was estimated to be over USD 700 million last year, and it is expected to surpass one billion by 2027 [6]. Numbers like that are bad for unproven treatments; they’re even worse for treatments that actually have been shown to be ineffective or no better than control interventions for several of its common indications [9, 12]. It’s that theme in particular that makes the work by Barreto et al. [2] so suitable for coverage in the Editor’s Spotlight/Take 5 section of CORR®. Most of us don’t treat patients with Achilles tendinopathy, and many of us don’t use PRP. But all of us need to recognize when to give up on a treatment that we think may be working [11], and this requires us to understand why discredited treatments persist in practice to begin with. Why, then, do they persist? Leaving aside financial incentives, as I would hate to think that those are driving our decisions, I believe the issue is that what we see in the office—patients who seem happy after a treatment—can be more powerful than what we read in journals, including in randomized trials. This shouldn’t be the case. There are many reasons for this, including the power of the placebo effect (which is large even for open-label placebos for pain treatment [4] and larger still for conventional or deceptive placebo interventions [13]) and the substantial impact of transfer bias: The missing are not doing as well as those who call or return to tell us they’re doing fine, and our follow-up on our own interventions in the office generally is short. If this doesn’t seem exactly right to you, think about whether the patients who come to you from your crosstown colleagues’ practices tend to be the happy ones or the unhappy ones. This is a rich topic, and one with implications for all of us, regardless of whether we use PRP or treat patients with Achilles tendinitis. For that reason, I’m excited to go deep on it with Dr. Kraychete, senior author of “Is Platelet-rich Plasma Effective in Treating Achilles Tendinopathy? A Meta-analysis of Randomized Clinical Trials” [2], in the Take 5 interview that follows. Take 5 Interview with Durval Campos Kraychete PhD, senior author of “Is Platelet-rich Plasma Effective in Treating Achilles Tendinopathy? A Meta-analysis of Randomized Clinical Trials” [2] Seth S. Leopold MD:Congratulations on this well-performed meta-analysis. What caused you to want to perform it? Durval Campos Kraychete PhD: Thank you for the opportunity to publish our work in CORR®. The idea for this meta-analysis emerged during one of our research group discussions, during which we explored the use of so-called “regenerative” techniques. In Brazil, over the past few years, we have witnessed a large rise in these approaches being marketed for various orthopaedic conditions, particularly in outpatient settings. These treatments often come at a high cost, even though they are not yet formally approved by regulatory agencies outside of research contexts. Having personally lived with chronic Achilles tendinopathy, I fully understanding how debilitating this condition can be, and I became particularly interested in evaluating PRP as a treatment option. This motivated us to delve deeper into the subject. We came across previous meta-analyses that found PRP to be ineffective, but we identified methodological issues in those studies that could limit their conclusions. The need for an updated, larger, and more comprehensive meta-analysis to reassess these findings became clear. Dr. Leopold:As I’d mentioned, it’s not as though yours is exactly a new finding; prior reviews found PRP to be ineffective for this indication [9, 14]. Yet the market for it has doubled since the first meta-analysis we published on this topic in 2018 [14]. Why might this be? Dr. Kraychete: I prefer to approach this issue with optimism, considering that the expanding PRP market may be influenced by factors beyond purely financial interests. As physicians, our primary responsibility is to prioritize the well-being of our patients. However, many of our colleagues rely on their clinical observations, which are often influenced by patients reporting positive outcomes after a procedure. This feedback is potentially shaped by placebo effects. It can obscure the true efficacy of the intervention and reinforce the belief, “In my practice, it works.” Moreover, patients who do not benefit from PRP treatment often do not return to their physicians, leaving only positive feedback in focus. This kind of incomplete follow-up distorts clinicians' perceptions of effectiveness, inflating the apparent benefits of the treatment and encouraging continued use of PRP, despite the limited evidence supporting its efficacy. This phenomenon is made more severe by the issue of publication bias in clinical research: Negative results often are not reported or published, further increasing the perception of efficacy and perpetuating the cycle. Addressing this bias is essential if we want to provide clinicians with a more balanced and evidence-based perspective on treatments like PRP. Dr. Leopold:This isn’t the only discredited treatment that remains in wide use; there are others, including surgical procedures that orthopaedic surgeons perform commonly [3, 10]. Articles in journals don’t seem to be having the desired effect, at least not in any reasonable timespan. What will work better to change common practice patterns? Dr. Kraychete: To address this, we need to rethink medical education, starting with undergraduate medical training and continuing through specialized practice. Residency programs should emphasize teaching residents how to become independent learners and critical thinkers. This includes fostering the ability to effectively search for, interpret, and apply medical evidence in their clinical decision-making. By helping residents develop these skills, training programs can increase the likelihood that their graduates employ—and that patients benefit from—care based on the most up-to-date evidence. Developing these skills also empowers physicians to critically evaluate and rethink outdated practices and to commit to continuous learning and improvement throughout their careers. It also is important to consider the roles these resident physicians will take on as they transition into the job market. They will need to navigate challenges such as the influence of digital media and competition from inadequately trained professionals. This issue is particularly pressing in countries like Brazil, where the rapid proliferation of medical schools and insufficient quality control have resulted in substantial variability in physician training. As a result, highly qualified professionals often find themselves competing in the same market as those with inadequate preparation. This undermines the application of evidence-based practices and complicates efforts to ensure consistent, high-quality care for patients. Addressing this issue through stricter regulation and oversight of medical education is crucial to fostering an environment where evidence-based approaches can truly thrive. Dr. Leopold:To what degree should our approaches vary by healthcare system (within a country) or among countries, in terms of encouraging changes to practice patterns? Dr. Kraychete: This is an excellent and thought-provoking question. There is a great gap between developed and developing countries in terms of healthcare resources, public policies, educational and cultural norms, and the programs that shape clinical practice. Ultimately, tailoring approaches to the specific characteristics of each healthcare system is essential for successfully encouraging changes in practice patterns. In publicly funded healthcare systems, changes in practice patterns may be more effectively driven through centralized policies, standardized guidelines, and educational campaigns. These systems often rely on evidence-based protocols to reduce variability in care and improve outcomes. However, there is often a large gap between what is covered in guidelines and what is actually implemented in everyday clinical practice. This gap is particularly pronounced in developing countries, where public systems are often overburdened with patients. This overload can lead to deviations from ideal clinical practices because of time and resource constraints. In contrast, in more privatized healthcare systems, where clinical decision-making is often decentralized and heavily influenced by market dynamics, the approach may need to be more individualized. Educating the physicians through continuing medical education programs and fostering shared decision-making with patients are likely to be more effective strategies. These efforts can help align clinical practices with the latest evidence while respecting the autonomy and preferences of both physicians and patients. Dr. Leopold:A common misconception is that a placebo is the same as “doing nothing” or “no treatment”; in fact, when it comes to enthesopathies and many degenerative tendon conditions (perhaps including Achilles pathophysiology) where a main endpoint of treatment is pain, placebos are extremely effective [10]. I’ll take the side of those who favor PRP for a moment: The fact that placebo effects are so large in this context may mask some actual biologic efficacy of PRP that we might learn from to refine and improve on this or other treatments based on principles of tissue healing or regeneration. To what degree might this be true and how might we get around this problem to see where or whether these treatments actually are helpful in some clinical settings? Dr. Kraychete: Thank you for the thoughtful perspective. Placebos have a unique ability to influence subjective experiences through complex neurobiological and psychological mechanisms, which is why placebo interventions can have a measurable effect on subjective outcomes like pain [7]. This phenomenon is particularly relevant in chronic pain conditions, where the patient’s perception of relief is influenced by factors such as trust in the practitioner, the ritual of the intervention, and prior experiences. This highlights the complexity of pain perception and the importance of accounting for placebo effects in clinical research. In patients with tendinopathies, where the intensity of pain often does not align with the degree of tissue damage, the placebo effect adds another layer of complexity to evaluating interventions like PRP. Randomized placebo-controlled trials are specifically designed to address this issue by balancing placebo responses across study groups, allowing researchers to isolate the true biological effects of an intervention. Such rigor is essential to accurately assess the clinical value of treatments like PRP and avoid over- or underestimating their efficacy. One aspect I found particularly compelling in a study by Kearney et al. [8] was those authors’ innovative approach to addressing a known problem in studies of this kind, related to the potential therapeutic effects of saline injections and dry needling in chronic Achilles tendinopathy. Both saline injections and dry needling have been theorized to provide therapeutic benefits beyond placebo, perhaps through mechanisms like localized trauma caused by the needle, which may stimulate a healing response, or pressure-volume changes within the tendon. These effects, while not targeting the underlying pathology in a biologically specific way, can still influence outcomes, making them inadequate as “true” placebos. To overcome this limitation, Kearney et al. [8] used sham injections as a control. In their study, a needle was inserted under the skin but not into the tendon, ensuring that neither the mechanical trauma associated with dry needling nor the potential physiological effects of saline could confound the results. This thoughtfully implemented control group allowed the researchers to isolate the placebo effect more effectively and assess whether PRP delivered benefits beyond that threshold. Despite this rigorous methodology and a sufficient sample size, the authors found PRP to be comparable to the sham group [8]. This finding strongly suggests that PRP does not deliver a biological effect in this context, and the study’s methodological approach is a good reminder about the importance of careful study design in evaluating treatments for tendinopathies. If PRP does indeed possess a distinct biological effect in such settings, studies like that one would be well-suited to reveal it. However, their findings, along with others in the field, suggest otherwise. Moving forward, I believe future research should prioritize more refined study designs, potentially those that incorporate biomarkers of tissue healing or regeneration to provide objective measures of biological activity. Additionally, large-scale studies with longer follow-up periods could provide more clarity, as they might capture subtle, longer-term effects that shorter trials might miss. This level of rigor is crucial to determining whether PRP or similar interventions can truly offer a meaningful clinical benefit.Durval Campos Kraychete PhD
Author: Seth S. Leopold
Institution: Clinical Orthopaedics and Related Research
Language: English
Subfield: Orthopedics and Sports Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W4409871515