The survivorship of the link endo-rotational hinge total knee arthroplasty: 5–12-year follow-up of 100 patients

There is a paucity of survival data reporting the medium to long-term outcome of the LINK® Endo-Model^® rotational hinge total knee arthroplasty (ERH-TKA). Such information is essential when counselling patients and predictors of survival would help inform patients of their likely outcome.

A series of patients, who received an ERH-TKA, with a minimum follow-up of 5 years, were retrospectively identified from an established arthroplasty database. Data were collected from paper and electronic patient records. This included patient demographics, indication for surgery, complication rates and revision status. Our primary outcome of interest was joint implant survival.

One hundred patients underwent an ERH-TKA over an 11-year period. There were 66 females and 34 males, with a mean age of 73.8 years and 67.6 years, respectively. Indications were classified into primary (n = 41), aseptic revision (n = 47) and two-stage infective revision (n = 12). The median follow-up was 8.2 (range 5–12) years. One-year implant survival amongst the cohort was 99%, falling to 95% at 5 years. Overall, there were eight revisions during the follow-up period. Considering only cases of aseptic failure, survival was 97% at 5 years and all failures occurred amongst revision cases. Implant failure was greater following revision arthroplasty but this was not statistically significant (p = 0.97). Cox regression analysis identified male sex to be the only independent predictor of failure (hazard ratio 1.75, 95% CI 1.04–31.82, p = 0.04) after adjusting for confounding variables.

The ERH-TKA has a good medium- to long-term survival rate but male patients are nearly twice as likely to undergo revision, compared to females, and should be made aware of this preoperatively.