Study finds, Long-term survival of a single-design condylar
The purpose of the study was to determine the long-term survivorship, functional outcomes of a single-design condylar constrained (CCK) TKA in primary and revision cases as well as to assess specific risk factors for failure. It was hypothesized that primary CCK TKA had a better survival than revision knees.

143 patients who have undergo a single design condylar restricted knee system revision of the TKA (n=119) or complex primary TKA (n=24) have been re-entered. The average follow-up was 11.8 years. The Kaplan-Meier survival estimates, together with the Cox multivariate Regression analysis, were used to examine implant survival to discover risk factors of failure. Oxford knee score was used to determine function (OKS).

--The implant survival was 86.4% after five, 85.5% after ten and 79.8% at 15 years.

--A reduced implant survivorship was found in males (HR 5.16), smokers (HR 6.53) and in obese patients (HR 2.26).

--Patients who underwent primary TKA had a higher revision-free implant survivorship compared to revision TKA at 15 years (100% vs. 76%).

--The main cause for re-revision was infection in 10% of all revision TKA performed with the CCK design included, while no case was revised for instability.

The median OKS was 39 (IQR 35–44) in 102 patients available for long-term functional outcome.

Finally, when used in primary TKA, the CCK implants are connected to excellent long-term survival; nevertheless, when employed during the TKA revolution, the survival was poorer. The risk of revision is greater for males, smokers, obese and patients. Although instability and aseptic loosening have not been so frequent, infection remains a major issue.