Platelet-rich plasma in equine joints still lacks a clear playbook: full analysis

Platelet-rich plasma is still firmly in the conversation for equine joint therapy, but the field is in a familiar place: strong clinical interest, uneven evidence, and no real agreement on the best way to prepare or use it. Recent systematic reviews and expert summaries describe PRP as widely used for equine osteoarthritis and joint disease, yet still difficult to evaluate because studies use different collection systems, platelet concentrations, leukocyte profiles, activation methods, and dosing approaches. (mdpi.com)

That tension has been building for years. Earlier reviews had already flagged the lack of consensus around PRP processing and the challenge of comparing patented kits with manual methods. More recent literature suggests the problem hasn’t been solved. A 2025 scoping review focused specifically on heterogeneity in equine PRP therapies found persistent variation in preparation methods and called for minimum reporting guidelines to improve reproducibility and clinical translation. (link.springer.com)

The newer evidence is useful, but still not definitive. A 2024 systematic review in Animals concluded that PRP may help reduce joint inflammation and support tissue repair in horses with osteoarthritis, but emphasized that the available studies are limited and inconsistent. A separate systematic review and meta-analysis published in 2024 similarly found conflicting evidence for PRP products in equine joint disease. Across the literature, a recurring issue is that many papers do not fully describe the final biologic being injected, making it hard to know whether positive or negative outcomes reflect PRP itself or the way that particular product was made. (mdpi.com)

Expert commentary from the field reinforces that point. In the 2025 AAEP Resort Symposium proceedings, PRP is described as difficult to classify because of differences in platelet concentration, white blood cell and red blood cell content, centrifugation steps, and activation methods. The same proceedings note that, despite extensive human knee osteoarthritis literature, support for intra-articular PRP use in horses remains limited and more research is needed to define its role in joint disease. The author also notes that in clinical practice, PRP is used primarily for soft tissues and only rarely as an intra-articular therapy. (aaep.org)

There are also signs the science is evolving beyond traditional autologous PRP. EquiManagement previously reported on work presented by Lauren Schnabel, DVM, PhD, DACVS, DACVSMR, describing a concentrated PRP lysate approach for osteoarthritis and joint infection applications. That work highlighted interest in platelet-derived products not just for growth factor delivery, but also for antimicrobial, anti-biofilm, and chondroprotective effects. Separately, FDA said in 2024 that PrecisePRP Equine, a concentrated platelet-in-plasma product for intra-articular injection, became the first such reviewed product for use in horses, a sign that the regulatory landscape around equine orthobiologics is also becoming more structured. (equimanagement.com)

Why it matters: For equine veterinarians, the current state of play argues for caution, specificity, and transparency. PRP may be attractive because it’s relatively accessible, often processed the same day, and aligns with demand for biologic options in performance horses. But the literature suggests clinicians shouldn’t treat all PRP products as interchangeable. Case selection, joint pathology, chronicity, competition schedules, and the exact formulation being used likely matter. That means conversations with pet parents and trainers should center on uncertainty as much as promise, especially when discussing expected duration of benefit, repeat injections, and how PRP compares with corticosteroids, ACS/IRAP, APS, or other orthobiologics. (aaep.org)

The bigger issue is evidence quality. If future studies consistently report baseline blood counts, final platelet yield, leukocyte content, activation method, dose, and injection schedule, the field may finally be able to identify which formulations work best for which indications. Until then, PRP remains a therapy with real biologic rationale and real clinical uptake, but incomplete standardization and incomplete answers. (mdpi.com)

What to watch: Watch for standardized reporting frameworks, validated commercial systems, and prospective equine trials that compare specific PRP formulations against established joint therapies on clear timelines and outcome measures. (mdpi.com)