Survival Up With Posterior Cruciate-Retaining TKR
Significantly lower risk of revision with posterior-cruciate-retaining total knee replacement
MONDAY, Nov. 21 (HealthDay News) -- Posterior cruciate-retaining total knee replacements (TKRs) show better survival at 15 years than posterior cruciate-stabilizing TKRs, according to a study published in the Nov. 16 issue of The Journal of Bone & Joint Surgery.
Matthew P. Abdel, M.D., from the Mayo Clinic in Rochester, Minn., and colleagues investigated 15-year survival in a retrospective review of 5,389 posterior cruciate-retaining and 2,728 posterior cruciate-stabilizing TKRs performed at a single institution between 1988 and 1998. Follow-up was carried out at one, two, and five years after the arthroplasty and every five years thereafter. The primary end point was aseptic revision surgery and Kaplan-Meier curves were used to estimate implant survival.
The investigators found that survival at 15 years was significantly better with posterior cruciate-retaining TKRs than with posterior cruciate-stabilizing TKRs (90 versus 77 percent). The 15-year survival for posterior cruciate-retaining TKR versus posterior cruciate-stabilizing TKR was 90 versus 75 percent in knees with preoperative deformity, and 88 versus 78 percent in knees without preoperative deformity. A significantly lower risk of revision was observed in knees with posterior cruciate-retaining TKR, after adjusting for age, gender, preoperative diagnosis, and preoperative deformity (hazard ratio, 0.5).
"In evaluating the implants used at our institution for total knee arthroplasty during the study period, posterior cruciate-retaining prostheses had significantly improved survival in comparison with posterior cruciate-stabilizing prostheses at 15 years," the authors write.