A Comparison of Total Knee Replacement Patients Using the Zimmer-Biomet Persona Total Knee System With Different Inserts

Summary

As demand for knee joint arthroplasties surge, improving long term patients' satisfaction and implant survivorship has become of utmost importance, as patients seek not only to alleviate their condition, but also return to their usual daily activities and sports. Implant type and design plays an important role in this, with many modern designs seeking to replicate the native knee's kinematics and alignment through mimicry of native knee biomechanics in its femoral components, tibial components, and polyethylene bearing inserts.

The Zimmer-Biomet Persona® Total Knee Cruciate-Retaining Femoral Component (CR Femur), used in conjunction with the kinematic alignment surgical technique, has been shown to produce better functional outcomes and improved patient satisfaction following total knee arthroplasty. More recently, Zimmer-Biomet introduced the Medial Congruent Bearing (MC Bearing) design to be used with the CR Femur; the design facilitates greater stability through increased anterior lip height compared to the original Cruciate Retaining Bearing (CR Bearing), thus allowing for greater anterior constraint and subluxation resistance that aids in activities requiring deeper flexion or full extension. However, the evidence that this will lead to better patient satisfaction and function is scarce, and requires further study to prove that the MC Bearing is a better insert choice to recommend to both surgeons and patients alike.

120 patients from Singapore General Hospital seeking primary total knee replacement surgery will be recruited for this study, and randomised in a 1:1 ratio to receive either the CR Bearing or the MC Bearing alongside the Zimmer-Biomet CR Femur implant. They will be followed up for two years post-operatively, and their outcomes recorded at specific milestones to be analysed for the impact of insert design on knee function, patient satisfaction and quality of life post-surgery.

Conditions

• Osteoarthritis, Knee
• Knee Osteoarthritis

Interventions

DEVICE

Medial Congruent Insert

The Medial Congruent Bearing (MC Bearing) design was introduced in 2016 for use with the Zimmer-Persona Cruciate-Retaining Femur: the design facilitates greater stability through increased anterior lip height compared to the original Cruciate Retaining Bearing (CR Bearing), allowing for greater anterior constraint and subluxation resistance that aids in full extension and deep flexion. Furthermore, the MC Bearing has been suggested for use in patients presenting with more complicated surgical histories (e.g prior high tibial osteotomies or patellectomies), whereas the original CR Bearing is strictly suggested for use only in patients undergoing knee surgery for the first time, where the posterior cruciate ligament may still be intact.

DEVICE

Cruciate-Retaining Insert

The Cruciate-Retaining Bearing (CR Bearing) design was launched together with the use of the Cruciate-Retaining Femoral Components (CR Femur) of the Zimmer-Biomet Persona® Total Knee system. The design not only stabilises the knee through medial conformity and anterior constraint, but also allows for freer and more natural deep flexion through freer movement of the lateral condyle.

Sponsors & Collaborators

• Singapore General Hospital

  lead OTHER

Principal Investigators

• Lincoln Liow · Singapore General Hospital

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Model

PARALLEL

Eligibility

Min Age

50 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2021-04-26

Primary Completion

2023-08-01

Completion

2023-08-01

Countries

• Singapore

Study Locations