出處： The Journal of Arthroplasty Vol.19 No.3 2004
＊ A prospective,randomized comparison of posterior cruciate-cruciate-retaining
( PCR ) and posterior stabilized ( PS ) total knee arthroplasty was conducted in 20 patients who underwent bilateral TKAs for osteoarthritis.
＊ All procedures were performed by a single surgeon. One knee was implanted with a PCR TKA, and a contralateral knee with a PS TKA. Both prosthetic designs were of the same TKA series, with comparable surface geometries.
＊ Patients had a clinical and radiographic evaluation at a mean of 31.7 months for
PCR TKAs and 30.6 months for PS TKAs postoperatively. There were no significant differences between the PCR and PS TKAs in postoperative knee scores.
＊ However, postoperative improvement in range of motion was significantly superior in the PS goup.
＊ Thisstudy included 20 patients ( 12 females and 8 males ) who underwent bilateral
TKAs for osteoarthritis between January 1998 and July 2000.Inclusion criteria were as follows: ( 1 ) bilateral osteoarthritic knees with similar roentgenographic grades; ( 2 ) bilateral TKAs performed with a time interval of less than 2 years; ( 3) correction of deformity achieved with retention of the PCL.
＊ Postoperatively, the patients remained in the hospital for 3 to 4 weeks for intensive rehabilitation.
＊ The mean age at the time of surgery was 74.3 years. All patients could be tracked for a minimum of 2 years,and no patients were lost to follow-up. Yhe average follow-up period was 31.7 months for the knees with PCR TKA and 30.6 months for those with PS TKA.
＊ Clinical outcome was assessed using the knee score and the knee function score of the knee society Score.
＊ In the clinical examination based on the knee society score, the mean preoperative knee scores were 42.8+9.9 for the PCR knees and 43.6 +10.1 for the PS knees, whereas the postoperative values were 89.8+7.2 and 89.5+ 8.9 respectively.
＊ Preoperative extension averaged -7.2 degrees in the PCR knees and -7.5 degrees in the PS knees. Postoperatively, the mean values were changed to -0..3 degrees

and -0.9 drgrees,respectively, with a significant improvement in both groups.
＊ Thus, the joint- line level was not affected by the resection of the PCL.
＊ ‘TKA has been shown to be an excellent treatment for patients with severe dysfunction and deformity of the knee.
＊ Proponents of PCL retention claim that it prevents posterior subluxation of the tibia,reduces shear stress, increases flexion and lever arm of the extensor mechanism by inducing femoral rollback upon flexion, and minimizes polyethylene abrasion by reducing stress applied to the articular surface.
＊ Hirsch et al observed a superior range of motion in a PS TKA. In the present study,prospective, randomized analysis of PCR and PS TKAs was performed for the patients who underwent bilateral TKAS.
＊ In conclusion,the present study compared the clinical outcome between the PCR and PS TKAs and showed a superior postoperative range of motion in the PS knee.
It is thought that one of the factors associated with flexion limitation in the PCR knee is unphysiologic tension of the PCL causing abnormal knee kinematics in flexion.