The role of platelet-rich plasma and stem cells in the management of osteoarthritis: Current evidence, clinical positioning, and translational challenges.

Abstract

Platelet-rich plasma (PRP) and mesenchymal stromal cell (MSC) therapies are among the most widely used regenerative interventions for knee osteoarthritis (OA). Despite being driven by a broadly similar regenerative concept, important differences in biological characteristics, evidence availability, and regulatory requirements mean that they should not be regarded as broadly comparable therapies. At the same time, conflicting findings from clinical trials and evidence syntheses continue to shape interpretation and clinical decision-making. Substantial heterogeneity across products, treatment protocols, patient populations, and study designs has further complicated the evidence base. Yet as public enthusiasm and commercialization continue to accelerate, these uncertainties are often overshadowed by simplified narratives and therapeutic expectations. Amid this uncertainty, clinical interpretation should prioritise reliable evidence over expectation-driven narratives. In this rapidly evolving landscape, regenerative therapies should be considered through a cautious, evidence-based, and guideline-informed lens. Current evidence does not support routine, indiscriminate, or first-line use of regenerative injections in knee OA. PRP may be discussed as a selective option for carefully selected patients after inadequate response to established conservative treatments, but uncertainty about the magnitude and durability of benefit, together with caveats related to reporting limitations, spin, and costs, should be clearly communicated to support shared decision-making. MSC-based and other cell-based therapies remain less established and require further rigorous evaluation before broader clinical adoption.