Mid-term outcomes of a novel liner design in kinematically-designed cruciate-retaining total knee arthroplasty

Medial dished (MD) liner designs for cruciate-retaining (CR) total knee arthroplasty (TKA) are a relatively novel development. MD tibial inserts have a more constraining medial side, which allows for more similar kinematics and function to a native knee.

To evaluate the clinical results and patient-reported outcomes after CR TKA procedures utilizing a kinematically designed medial dish system.

A multicenter, retrospective cohort review of 139 primary elective TKAs utilizing a kinematically designed CR Knee System (JOURNEY™ II CR MD; Smith and Nephew, Memphis, TN, United States) at three different institutions with a minimum of two years of follow-up. Demographic information, clinical outcomes, and patient-reported outcome measures were collected and analyzed.

With up to 3.7 years from surgery, overall implant survivorship was 98.6%. There were significant postoperative increases in the average Knee Injury and Osteoarthritis Outcome Score for Joint Replacement scores (17.4 at 6 months, 26.1 points at two years or more, P < 0.001).

The combination of high implant survivorship and substantial improvements in patient-reported outcome measures suggests that the medial dish tibial insert represents a safe and effective option within TKA. Additional investigation is necessary to evaluate the long-term survivorship of this design.