95. CEDIOR TOTAL KNEE PROSTHESIS: 10-YEAR OUTCOME

Abstract

Purpose of the study: The purpose of this retrospective study was to present the outcomes observed with the Cedior total knee arthroplasty (TKA), and in particular an embedded patellar implant fixed without cement and cemented titanium backed base plate with a press fit stem.

Material and methods: From January 1993 to December 1996, 155 TKA were implanted in 143 patients for degenerative disease of the knee joint. At last follow-up, 55 patients had died, 28 were lost to follow-up 14 were contacted by phone, and 46 were reviewed clinically. Mean age was 62 years (62–80), BMI: 29.9 (22.6–38.2). Mean follow-up was 12 years (10–13). Posterior stabilised implants were used for 33% of the knees and the posterior cruciate was preserved in 67%. For all knees, the thickness of the polyethylene was > 6mm. Outcome was assessed clinically with the IKS, WOMAC, and Charnley scores and radiographically on the basis f lucent lines, osteolysis, and residual misalignment as measured on the standard films and goniometry. Survival was determined with the Greenwood method.

Results: Two patients (2 posterior stabilised TKA) with residual varus > 6 (> 15 preoperatively) were revised for loosening. At last follow-up, the postoperative IKS was 164, the WOMAC 28. Two patients were dissatisfied. Radiographically residual alignment was less than 3 in 56%, 3 to 6 in 41% and > 6 in 3%. For the femur, there were two lucent lines in a single zone. For the tibia, six lines in zone 7, none around the stem. For the patella, two implants presented significant asymptomatic osteolysis and there were two spontaneous (5 and 8 years) and asymptomatic fractures. Survival was 98.1±4.6% for revision and 96.2±6.9% for aseptic loosening.

Discussion: Our results are comparable with 10-year outcomes published in the literature where the survival has ranged from 92% to 99%. The titanium back cemented under the bas without cementing the sanded stem provides satisfactory results. The two loosening occurred for a residual varus > 6. The embedded, non-cemented patellar implant gave satisfactory results but the two cases of osteolysis led us to propose cementing.