Synopsis

The overall goal of this case study is to analyze the role of the transverse ligament (TL) in menisci & cartilage mechanics in the Open Knee(s) - Generation 1 model.

Use Case

The case is based on experimental studies investigating the role of the transverse ligament in menisci translation and menisci/cartilage stress distributions. Muhle, 1999 explored menisci kinematics in the presence and absence of the transverse ligament, and found that the TL had a restricting effect on translation of the anterior horn of the medial meniscus. The use cases aims for illustrating the capacity of the Open Knee(s) - Generation 1 model to analyze the function of a ligament via in silico modeling techniques.

Simulation Aims

• To understand the role of the transverse ligament in menisci & cartilage mechanics during passive flexion & compression (primary)

• To explore the correspondence of Open Knee(s) simulation against experimental passive flexion data of the knee (secondary)

Model

The model is based on Open Knee(s) - Generation 1 model, which was updated for FEBio version 2.X (release will include in situ strains and material properties for meniscal attachments):

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

Inputs

Prescribed movement and loading of the tibiofemoral joint representative of experimental data from Muhle, 1999:

• 0, 30, 60, 90 degrees flexion (primary)

Outputs

• Time histories of menisci kinematic, stress behavior (primary)
• Time histories of cartilage stress-strain behavior (primary)
• Time histories of kinematics-kinetics of the tibiofemoral joint (six degrees of freedom) (secondary)
  • flexion torque
  • internal/external rotation
  • varus/valgus
  • anterior/posterior translation
  • medial/lateral translation
  • compression/distraction

Simulation Conditions

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

Team Members

• Ahmet Erdemir - study planning, outline of publications
• Omar Gad - execution of simulations and post-processing, lead authorship in publications
• Craig Bennetts - assisting simulations, scripting for pre-/post-processing, support to document model in publications
• Snehal Chokhandre - support to document model in publications

Progress

Source Code Repository

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

Data

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

Model Customization

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

Simulations

Post-Processing

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

Publications

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

References

1. Muhle et al., 1999. Invest Radiol, 34(9) 558-565.

2. Poh et al., 2010. The Knee, 19(2012), 135-139.