TableOfContents

Synopsis

The overall goal of this case study is to provide the utility of Open Knee(s) - Generation 1 model for reproducing the outcome of a clinical test, the pivot shift, for evaluating mechanical function of the anterior cruciate ligament.

Use Case

The case is based on reproduction of a pivot shift loading scenario in a tibiofemoral joint model. The loading scenario was measured in a cadaver knee during pivot shift tests conducted by an orthopaedic surgeon. In follow-up robotics testing, this loading profile was adjusted for robotics testing of intact, ACL deficient, and ACL reconstructed knees. The use case aims for illustrating the capacity of the Open Knee(s) - Generation 1 model to reproduce the clinical differentiation of intact and ACL deficient knee in a virtual sense.

Simulation Aims

• To understand the role of ACL for stabilization of the joint during pivot shift testing (primary)
• To explore the correspondence of Open Knee(s) simulation against robotics prescribed pivot shift loading of various knees (secondary)

Model

The model is based on Open Knee(s) - Generation 1 model, which was updated for FEBio version 2.1:

• https://simtk.org/svn/openknee/_gen1/src/tf_joint_FEBio_v2.feb

Inputs

Outputs

Simulation Conditions

Six degrees of freedom loading of tibiofemoral joint (prescribed flexion; internal/external rotation and varus/valgus moments; anterior/posterior, medial/lateral and compression/distraction forces):

• with intact ACL
• without the ACL (very low stiffness for convenient modeling and simulation workflow)

Team Members

Progress

Source Code Repository

https://simtk.org/svn/openknee/app/PivotShift/

Data

https://simtk.org/svn/openknee/app/PivotShift/dat/

Model Customization

https://simtk.org/svn/openknee/app/PivotShift/src/

Simulations

Post-Processing

https://simtk.org/svn/openknee/app/PivotShift/sol/

Publications

https://simtk.org/svn/openknee/app/PivotShift/doc/

References