Knee joint biomechanics in ovine models of post-traumatic osteoarthritis
Creators: name: Shekarforoush, Seyed Mohammad Mehdi
Publisher: name: Graduate Studies
Year: 2018
Subjects: subject: Post traumatic osteoarthritis
subject: Knee Injury
subject: ACL injury
subject: Knee
subject: Ligament loads
subject: knee kinematics
subject: Joint angular velocity
subject: Joint linear velocity
subject: Applied Mechanics
subject: Engineering--Biomedical
subject: Engineering--Mechanical

description: Post-traumatic osteoarthritis (PTOA) is a sub-type of osteoarthritis, which can develop after injury to a joint and to date, many aspects of the etiology of the disease remain unclear. The main objective of this research was to quantify the subtle changes in the kinematic and the kinetic variables in the ovine stifle (knee) joint following different types of ligamentous and meniscal injury, and to investigate possible consequences of those biomechanical changes on gross morphological osteoarthritis-like damage in the joints. Overall, there was a high degree of inter-subject variability in the measured variables. We found different degrees of instabilities in the 6 degree-of-freedom kinematics and finite helical axis variables of the joints after ligamentous and meniscal injuries. Nevertheless, we did not detect correlations between the magnitudes of the changes in the kinematic variables with significant change and osteoarthritis-like damage in the joints. The kinematic analyses also suggest that the absolute change of the tibiofemoral translation vector could be an important risk factor for osteoarthritis development after ligament injuries. The magnitude of the joint angular velocities was decreased in extension during swing after different types of injury and the reduction was correlated with the morphological damage for two multiple ligament injury groups. We also found a weak correlation between the increase in some components of the tibiofemoral sliding velocity during stance after partial- anterior cruciate ligament (ACL) and medial collateral ligament (MCL) transection (p-ACL/MCL Tx) and the joint morphological damage in both the lateral and medial compartments of the joint. Kinetic analyses demonstrated a reduction in LCL load, slight increase in the PCL load and a consistent increase in the healed MCL load, especially during the stance stage of gait, after p-ACL/MCL Tx. Overall, the medial meniscus carried a higher magnitude of load than the lateral meniscus and the magnitude of the medial meniscus load was increased consistently in the animals through some parts of the gait cycle, 20 weeks after p-ACL/MCL Tx. No correlation was detected between variation in the meniscal loads and morphological damage in the joints, suggesting that the increase in the meniscal load after p-ACL/MCL Tx might not result in visible post-traumatic osteoarthritis damage in the short term after injury in an ovine model. Finally, we did not detect any consistent correlation between the changes in the ligament or meniscal loads and changes in analyzed kinematic variables, suggesting that ligamentous and meniscal loading regimes are not linear functions of different kinematic variables. The results improve our insight on how joint mechanical abnormalities can result in the development of post-traumatic osteoarthritis.