Objective To investigate the influence of cartilage degeneration grades of patellar on the clinical outcomes after total knee arthroplasty (TKA) without patellar resurfacing.Methods 151 patients performed TKA without patellar resurfacing from February 2007 to January 2010 were retrospective studied.There were 65 males and 86 females,with the mean age of 65±5.0 years (range,56-82 years).The mean duration of follow-up was 3.5 years (range,2-5 years).Intraoperatively,the cartilage degeneration was classified according to Outerbridge classification.At the final follow-up,the patients' satisfaction was evaluated,and the incidence of anterior knee pain was assessed using visual analogue scale (VAS).If VAS was more than 3 points,patient was defined suffered anterior knee pain.Compare KSS and patella score of patients with different grades of cartilage degeneration.Results The articular cartilage of the patella was graded according to Outerbridge:grade Ⅰ in 18 patients,grade Ⅱ in 36 patients,grade Ⅲ in 62 patients,and grade Ⅳ in 35 patients.At the final follow-up,the patients' satisfaction rate and the anterior knee pain rate was 96.7％ 046/151) and 4.0％ (6/151),respectively.In the patients with different grades of cartilage degeneration,the patient satisfaction rate (H=5.54,P=0.14),anterior knee pain rate (H=0.56,P=0.91),KSS (knee score:F=1.95,P=0.12； function score:F=2.11,P=0.10) and patella score (F=1.35,P=0.26) were not found to be significantly difference.Conclusion The differentiae grades of cartilage degeneration may not affect the clinical outcomes of TKA.TKA without patella resurfacing appears to be a reasonable option for degenerative osteoarthritis.