Effect of patellar tendon release on squatting characteristics of tibiofemoral joint after total knee arthroplasty: a simulation analysis

Abstract

BackgroundThe objective of this paper was to study the patellar tendon release’s effect on the squat movement characteristics of the tibiofemoral joint after TKA (total knee arthroplasty).MethodsThe dynamic FEM(finite element model) of the human knee joint with 30% release of the upper end, lower end and both ends of the patellar tendon after TKA was established respectively, and the knee tibiofemoral joint of the squat movement simulation analysis.ResultsThe results of simulation show that in the release of three different parts, comparing with the results of no release simulation, the average of lateral translation, superior translation, posterior translation, and the adduction of the femur relative to the tibia decreased by 20%, 17%, 17%, and 12%, respectively.ConclusionThe average of external rotation of the femur relative to the tibia increased 24%. By comparing the data after patellar tendon release and no release one, it can be concluded that the flexion degree of femur relative to the tibia was 4° on average more than no release. Moderate release of the patellar tendon during TKA surgery is beneficial to improve the range of motion (ROM) of the femur relative to the tibia.

Validation of a novel finite-element model for evaluating patellofemoral forces and stress during squatting after posterior-stabilized total knee arthroplasty

“…Additionally, our simulation was designed to ana- lyze extensor mechanism reaction forces and patellofemoral stress as output data, thus patellofemoral kinematics were not collected. Lastly, model inputs such as the patellar retinaculum [31,32], hamstring tendons [33] and more complex collateral ligaments models [34] could be incorporated to provide more realistic patellofemoral behavior during squatting motion. In addition to some intraoperative tools [35], a preoperative computational simulation tool could predict individual patellofemoral forces and contact pressure with respect to implant position or patient-specific anatomy, providingdata that would help the surgeon in planning the TKA implantation.…”