Platelet-Rich Plasma: The PAW Classification System

• Published in: Arthroscopy Vol. 28; no. 7; pp. 998 - 1009
• Main Authors: DeLong, Jeffrey M., Russell, Ryan P., Mazzocca, Augustus D.
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Inc 01.07.2012; Elsevier
• Subjects: Arthroscopy; Biological and medical sciences; Blood Buffy Coat; Classification - methods; Endoscopy; Guided Tissue Regeneration - methods; Humans; Investigative techniques, diagnostic techniques (general aspects); Leukocyte Count; Leukocytes; Medical sciences; Orthopedic Procedures - methods; Orthopedic surgery; Orthopedics; Platelet Activation; Platelet Count; Platelet-Rich Plasma - chemistry; Platelet-Rich Plasma - cytology; Platelet-Rich Plasma - metabolism; Surgery (general aspects). Transplantations, organ and tissue grafts. Graft diseases; Arthroscopy; Orthopedic surgery; Treatment; Endoscopy; Classification; Growth factor
• ISSN: 0749-8063; 1526-3231; 1526-3231
• DOI: 10.1016/j.arthro.2012.04.148

Platelet-rich plasma (PRP) has been the subject of hundreds of publications in recent years. Reports of its effects in tissue, both positive and negative, have generated great interest in the orthopaedic community. Protocols for PRP preparation vary widely between authors and are often not well documented in the literature, making results difficult to compare or replicate. A classification system is needed to more accurately compare protocols and results and effectively group studies together for meta-analysis. Although some classification systems have been proposed, no single system takes into account the multitude of variables that determine the efficacy of PRP. In this article we propose a simple method for organizing and comparing results in the literature. The PAW classification system is based on 3 components: (1) the absolute number of Platelets, (2) the manner in which platelet Activation occurs, and (3) the presence or absence of White cells. By analyzing these 3 variables, we are able to accurately compare publications.