Lateral-stabilized total knee arthroplasty enables design-specific kinematic behavior consistent with key...

Area of Science:

• Orthopedic Surgery
• Biomechanical Engineering
• Arthroplasty Design

Background:

• Anterior knee pain (AKP) is a significant cause of dissatisfaction after total knee arthroplasty (TKA).
• Non-physiological knee kinematics and patellar maltracking are frequently associated with AKP post-TKA.
• Incorporating in vivo knee kinematics into TKA design may reduce negative outcomes.

Purpose of the Study:

• To evaluate the clinical outcome of a novel TKA system (5C® LATic) designed using in vivo knee kinematics.
• To assess the kinematics of the 5C® LATic TKA system in patients.

Main Methods:

• Retrospective study including eleven patients treated with the 5C® LATic TKA system.
• In vivo fluoroscopic measurements of 3D TKA motion during a loaded lunge from extension to maximal flexion at 12 months post-surgery.
• Patient-reported outcome measures including Knee Society Score (KSS), Function Joint Score (FJS), and Hospital for Special Surgery Knee Score (HFKS).

Main Results:

• The 5C® LATic system exhibited lateral stability and reduced anterior medial compartment movement, with femoral component external rotation on the tibial plateau.
• Consistent posterior movement of the femoral component's frontal aspect was observed until maximal flexion.
• All patients reported significant improvements in KSS, FJS, and HFKS scores compared to their preoperative state, with high overall satisfaction.

Conclusions:

• The 5C® LATic TKA system demonstrated design-based kinematics consistent with its intended biomechanical goals.
• The observed kinematics, including external rotation and posterior femoral translation, may contribute to improved patellar tracking.
• These kinematic features hold potential for reducing anterior knee pain and enhancing patient satisfaction after TKA.