Medial Stabilised Total Knee Arthroplasty: Definition and Performance

Abstract

Medial-stabilised total knee arthroplasty (MS-TKA) usage has increased significantly over the past decade with encouraging results. MS-TKA mimics the natural knee kinematics, providing superior antero-posterior stability as compared to cruciate-retaining or posterior-stabilised designs. Its proponents suggest that MS-TKA may provide the solution to the residual dissatisfaction seen in many patients following knee replacement surgery. The literature was reviewed for critical analysis of the evidence for the biomechanics of the native knee and the clinical outcomes for MS-TKA. The history of the development of the medial-stabilised knee was also reviewed. MS-TKA were found generally to have similar revision rates to non-MS-TKA. Studies of knee function found either similar or improved function, which may be due to increased AP stability and a lack of paradoxical movement of femur over tibia which is seen in CR and PS designs. This review highlights the key design features needed for a total knee arthroplasty to be termed as a medial-stabilised design, summarises current clinical and kinematic evidence including an overview of its development over the past three decades and sets out the next steps needed for meaningful evaluation of long-term real-world data of individual MS-TKA implants. With longer and more detailed follow-up data emerging as MS-TKA becomes more popular, a more thorough analysis of their performance will soon be possible.