Biomechanics of the medial meniscus in the osteoarthritic knee joint

Karol Daszkiewicz; Piotr Łuczkiewicz

doi:10.7717/peerj.12509

Biomechanics of the medial meniscus in the osteoarthritic knee joint

PeerJ. 2021 Nov 24:9:e12509. doi: 10.7717/peerj.12509. eCollection 2021.

Authors

Karol Daszkiewicz¹, Piotr Łuczkiewicz²

Affiliations

¹ Department of Mechanics of Materials and Structures, Faculty of Civil and Environmental Engineering, Gdańsk University of Technology, Gdańsk, Poland.
² II Department of Orthopaedics and Kinetic Organ Traumatology, Medical University of Gdańsk, Gdańsk, Poland.

Abstract

Background: Increased mechanical loading and pathological response of joint tissue to the abnormal mechanical stress can cause degradation of cartilage characteristic of knee osteoarthritis (OA). Despite osteoarthritis is risk factor for the development of meniscal lesions the mechanism of degenerative meniscal lesions is still unclear. Therefore, the aim of the study is to investigate the influence of medial compartment knee OA on the stress state and deformation of the medial meniscus.

Methods: The finite element method was used to simulate the stance phase of the gait cycle. An intact knee model was prepared based on magnetic resonance scans of the left knee joint of a healthy volunteer. Degenerative changes in the medial knee OA model were simulated by nonuniform reduction in articular cartilage thickness in specific areas and by a decrease in the material parameters of cartilage and menisci. Two additional models were created to separately evaluate the effect of alterations in articular cartilage geometry and material parameters of the soft tissues on the results. A nonlinear dynamic analysis was performed for standardized knee loads applied to the tibia bone.

Results: The maximum von Mises stress of 26.8 MPa was observed in the posterior part of the medial meniscus body in the OA model. The maximal hoop stress for the first peak of total force was 83% greater in the posterior horn and only 11% greater in the anterior horn of the medial meniscus in the OA model than in the intact model. The reduction in cartilage thickness caused an increase of 57% in medial translation of the medial meniscus body. A decrease in the compressive modulus of menisci resulted in a 2.5-fold greater reduction in the meniscal body width compared to the intact model.

Conclusions: Higher hoop stress levels on the inner edge of the posterior part of the medial meniscus in the OA model than in the intact model are associated with a greater medial translation of the meniscus body and a greater reduction in its width. The considerable increase in hoop stresses shows that medial knee OA may contribute to the initiation of meniscal radial tears.

Keywords: Hoop stress; Knee biomechanics; Knee osteoarthritis; Medial meniscus; Meniscal extrusion; Meniscal tear.

Grants and funding

The publication of study was financed by the Faculty of Civil and Environmental Engineering, Gdańsk University of Technology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.