PRP or not PRP: Is the debate surrounding platelets-based blood-derived products evolving?

Abstract

The increasing interest in biologic treatments for musculoskeletal disorders has led to the advancement of orthobiologics, particularly in non-operative care through injectable therapies. However, defining these treatments clearly is crucial for proper clinical application. Orthobiologics include biologic substances that enhance healing, such as cell-based therapies and blood-derived products. Among these, platelet-rich plasma (PRP) is widely used, but its classification remains complex due to variations in preparation methods, platelet concentration, leucocyte content, and activation techniques. Strictly, the term 'PRP' refers to plasma enriched in platelets relative to baseline blood levels. Yet, scientific debate persists regarding whether platelet count or enrichment is more significant in clinical outcomes. Additionally, leucocyte-rich and leucocyte-poor PRPs offer different therapeutic advantages depending on the target tissue, complicating standardization. Similarly, the presence of red blood cells is generally discouraged, given their association with joint inflammation. Beyond the classical 'PRP' formulations, alternative blood-derived products offer distinct biological effects. A standardized classification system is therefore essential for research and clinical application, emphasizing precise documentation of products' characteristics, including platelet count, activation state and bioactive molecule interactions. Understanding these variables and their impact on patient-specific conditions will refine orthopaedic regenerative strategies and optimize treatment efficacy.