Platelet-rich fibrin and cartilage granules facilitate cartilage repair Kuo T-F et al. ACKNOWLEDGMENTS The authors wish to thank Wan Fang Hospital at Taipei Medical University (Key Research Grant 99wf-eva-05) for supporting this project. AUTHOR CONTRIBUTIONS T–F Kuo conceived and designed the study, prepared the animals for surgery and histology, and was responsible for the collection, analysis and interpretation of data. M–F Lin conceived and designed the study, was responsible for the magnetic resonance images, and collection, analysis and interpretation of data. WP Chan conceived and designed the study, was responsible for the critical revision for important intellectual content and for the draft of the manuscript. R–J Su prepared the animals for surgery and histology, and collected the data. Y–H Lin was responsible for the analysis and interpretation of data. H–W–Lin was responsible for the statistical analysis. Y–C Lin was responsible for the literature revision and for the draft of the manuscript. All the authors have given approval of the version to be published. T–F Kuo and M–F Lin contributed equally to this work and both acted as first author. REFERENCES 1. Grande DA, Pitman MI, Peterson L, Menche D, Klein M. The repair of experimentally produced defects in rabbit articular cartilage by autologous chondrocyte transplantation. J Orthop Res. 1989;7:208–18, doi: 10.1002/jor.1100070208. 2. Brittberg M, Lindahl A, Nilsson A, Ohlsson C, Isaksson O, Peterson L. Treatment of deep cartilage defects in the knee with autologous chondrocyte transplantation. N Engl J Med. 1994;331:889–95, doi: 10. 1056/NEJM199410063311401. 3. Hendriks JAA, Adesida AB. Isolation of cells. US Patent Application 20100144036. 4. Murray TG, Parker RD. Restoring cartilage defects: microfracture to autologous chondrocyte implantation using investigational 3D scaffold. Orthopedics. 2007;30:766–7. CLINICS 2011;66(10):1835-1838 5. Simonpieri A, Choukroun J, Girard MO, Ouaknine T, Dohan D. Immediate post-extraction implantation: interest of the PRF. Implantodontie. 2004;13:177–89, doi: 10.1016/j.implan.2004.06.004. 6. Choukroun J, Diss A, Simonpieri A, Girard MO, Schoeffler C, Dohan SL, et al. Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part IV: clinical effects on tissue healing. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006;101:e56–60, doi: 10.1016/j.tripleo.2005.07.011. 7. Dohan DM, Choukroun J, Diss A, Dohan SL, Dohan AJ, Mouhyi J, et al. Platelet-rich fibrin (PRF): a second-generation platelet concentrate. Part I: technological concepts and evolution. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2006;101:e37–44, doi: 10.1016/j.tripleo.2005.07.008. 8. Mainil-Varlet P, Van Damme B, Nesic D, Knutsen G, Kandel R, Roberts S. A new histology scoring system for the assessment of the quality of human cartilage repair: ICRS II. Am J Sports Med. 2010;38:880–90, doi: 10.1177/0363546509359068. 9. Mainil-Varlet P, Aigner T, Brittberg M, Bullough P, Hollander A, Hunziker E, et al. International Cartilage Repair Society. Histological assessment of cartilage repair: a report by the Histology Endpoint Committee of the International Cartilage Repair Society (ICRS). J Bone Joint Surg Am. 2003;85-A Suppl 2:45–57. 10. Chiang H, Kuo TF, Tsai CC, Lin MC, She BR, Huang YY, et al. Repair of porcine articular cartilage defect with autologous chondrocyte transplan- tation. J Orthop Res. 2005;23:584–93, doi: 10.1016/j.orthres.2004.11.003. 11. Lee HJ, Choi BH, Jung JH, Zhu SJ, Lee SH, Huh JY, et al. Maxillary sinus floor augmentation using autogenous bone grafts and platelet-enriched fibrin glue with simultaneous implant placement. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007;103:329–33, doi: 10.1016/j.tripleo. 2006.03.010. 12. Filova´ E, Jel´ınek F, Handl M, Lytvynets A, Rampichova´ M, Varga F, et al. Novel composite hyaluronan/type I collagen/fibrin scaffold enhances repair of osteochondral defect in rabbit knee. J Biomed Mater Res B Appl Biomater. 2008;87:415–24. 13. White LM, Sussman MS, Hurtig M, Probyn L, Tomlinson G, Kandel R. Cartilage T2 assessment: differentiation of normal hyaline cartilage and reparative tissue after arthroscopic cartilage repair in equine subjects. Radiology. 2006;241:407–14, doi: 10.1148/radiol.2412051750. 14. Chou MC, Tsai PH, Huang GS, Lee HS, Lee CH, Lin MH, et al. Correlation between the MR T2 value at 4.7 T and relative water content in articular cartilage in experimental osteoarthritis induced by ACL transection. Osteoarthritis Cartilage. 2009;17:441–7, doi: 10.1016/j.joca. 2008.09.009. 1838