Validation of a computational knee joint model using an alignment method for the knee laxity test and computed...

Area of Science:

• Biomechanics
• Computational modeling
• Medical imaging

Background:

• Computational models aid clinical decisions but kinematic validation is challenging.
• Medical imaging offers improved visualization of knee joint kinematics.
• Previous models often relied on published data for validation.

Purpose of the Study:

• To perform kinematic validation of a subject-specific computational knee joint model.
• To compare the computational model against subject's medical imaging data.
• To ensure identical laxity conditions between the model and imaging.

Main Methods:

• Applied anterior-posterior drawer (90° flexion) and varus-valgus (20° flexion) laxity tests.
• Utilized stress radiographs, a Telos device, and computed tomography (CT).
• Matched computational model loading conditions to laxity test conditions in medical imaging.

Main Results:

• Computational model demonstrated knee laxity trends consistent with CT images.
• Negligible differences observed due to indirect application of in vivo material properties.
• Successful kinematic validation of the subject-specific model.

Conclusions:

• Computed tomography-based laxity testing precisely measures knee joint translation and rotation.
• This methodology validates subject-specific computational knee models.
• Enhances accuracy in clinical decision-making for knee joint conditions.