A 15 to 17-year follow-up of the Kinemax total knee replacement

BACKGROUND: There is a paucity of long-term data concerning the pre- and postoperative patient reported function of total knee replacement. The aim of this study was to determine the mortality, implant survivorship, patient reported function and satisfaction in a cohort of 114 patients, from a single centre, who received a Kinemax total knee replacement more than 15 years ago.

METHODS: Patients completed a questionnaire incorporating validated disease- and joint-specific scores, patient satisfaction and overall health preoperatively, at three months, one year, two years and a minimum of 15 years following surgery. NHS National Strategic Tracing Service, hospital and primary care records were used to establish mortality and for implant survivorship in deceased patients.

RESULTS: Forty five patients were alive at final follow-up. The survivorship of the cohort with revision of the TKR as the endpoint was 84%. Four cases were revised for wear, three for loosening and one for peri-prosthetic fracture. There was a significant improvement in WOMAC Pain, Function and Stiffness Scores, Oxford Knee Score and Self-Administered Patient Satisfaction Scale between pre-operative and all post-operative time points, although patient satisfaction had decreased significantly by the time of final follow-up.

CONCLUSION: In this cohort, the Kinemax TKR showed survivorship of 84% at 16.3 years with functional scores demonstrating a high level of patient satisfaction at all follow-up time points.

LEVEL OF EVIDENCE: 2 - Prospective Cohort Study.