3Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries[J]. Clin Orthop, 1985, 198: 43- 49.
4Balazs EA, Bloom G, Swann G. Fine structure and glycosamininoyly can content of the surface layer of articular cartilage[J]. Fed Proc, 1996, 25: 1813.
5Astman R,Asehe,Bloeh D. Development of erite ria for the classification and reporting of osteoarthrltis,classification of osteoarthritis of knee[J].Arthritis and Rheumatism,1986.1039.doi:10.1002/art.1780290816.