An EMG-assisted Muscle-Force Driven Finite Element Analysis Pipeline to Investigate Joint- and Tissue-Level Mechanical Responses in Functional Activities: Towards a Rapid Assessment Toolbox

Abstract

Joint tissue mechanics (e.g., stress and strain) are believed to have a major involvement in the onset and progression of musculoskeletal disorders, e.g., knee osteoarthritis (KOA). Accordingly, considerable efforts have been made to develop musculoskeletal finite element (MS-FE) models to estimate highly-detailed tissue mechanics that predict cartilage degeneration. However, creating such models is time-consuming and requires advanced expertise. This limits these complex, yet promising MS-FE models to research applications with few participants and making the models impractical for clinical assessments. Also, these previously developed MS-FE models are not assessed for any activities other than the gait. This study introduces and validates a semi-automated rapid state-of-the-art MS-FE modeling and simulation toolbox incorporating an electromyography (EMG) assisted MS model and a muscle-force driven FE model of the knee with fibril-reinforced poro(visco)elastic cartilages and menisci. To showcase the usability of the pipeline, we estimated joint- and tissue-level knee mechanics in 15 KOA individuals performing different daily activities. The pipeline was validated by comparing the estimated muscle activations and joint mechanics to existing experimental data. Also, to examine the importance of EMG-assisted MS analyses, results were compared against outputs from the same FE models but driven by static-optimization-based MS models. The EMG-assisted MS-FE pipeline bore a closer resemblance to experiments, compared to the static-optimization-based MS-FE pipeline. More importantly, the developed pipeline showed great potentials as a rapid MS-FE analysis toolbox to investigate multiscale knee mechanics during different activities of individuals with KOA.

Model Properties and Clinical Application in the Finite Element Analysis of Knee Joint: A Review

“…Esrafilian et al simplified the muscle model and used spring elements to simulate the muscle. 58 Some scholars have also modeled the muscle as a two-dimensional fiberreinforced structure containing membrane and spring elements. 59,60 Tendons are similar in structure and function to ligaments.…”

“…Tendons can be modeled with spring elements and hyperelastic material models, with the spring elements being widely used. 58,61 Wang et al compared three tendon models: Marlow, Neo-Hookean, and linearly elastic models. They found that the Marlow model was more consistent with the experimental mechanical data of the patellar tendon.…”

“…61 Amir et al conducted a finite element analysis of daily and rehabilitation activities in patients with knee OA and found that the medial tibia had greater mechanical stress than the lateral in most daily activities, a result that matched the higher prevalence of OA in the medial compartment. 58 The rehabilitation exercise of knee extension could effectively strengthen the quadriceps muscle. The stress on the lateral tibial cartilage was greater than that on the medial side, suggesting that this rehabilitation activity could have a promising clinical future.…”

“…The stress on the lateral tibial cartilage was greater than that on the medial side, suggesting that this rehabilitation activity could have a promising clinical future. 58 Knee FEM can also serve as an aid in sports and training, helping athletes to engage in safer training and have better sports performance. Yu et al evaluated the patellofemoral joint loading during the directional lunges of badminton players through MS-FE modeling, finding that the proper patellofemoral joint loading was more significant when righthanded players were making a left-backward lunge.…”

Mechanobiochemical finite element model to analyze impact-loading-induced cell damage, subsequent proteoglycan loss, and anti-oxidative treatment effects in articular cartilage

“…To gather these data, we will conduct new ex vivo experiments. Combining the calibrated cell-tissue level model into state-of-the-art joint-level degeneration models with patient-specific joint geometries, contact forces and inflammation [44,68], the model could then be used to guide the most optimal treatment strategies to mitigate PTOA progression. 20…”