In-Silico Models to Investigate Bone Marrow Lesions.

Kayode, O.; Mengoni M.; Conaghan P.; Wilcox R.

In-Silico Models to Investigate Bone Marrow Lesions.

All Authors

Kayode, O.

Mengoni M.

Conaghan P.

Wilcox R.

LTHT Author

Conaghan, Philip

LTHT Department

Rheumatology

Publication Date

2021

Item Type

Conference Abstract

Abstract

Introduction: Osteoarthritis (OA) affects more than four million people in the UK alone(1). Bone marrow lesions (BMLs) are one feature of subchondral bone involvement in OA. BMLs are radiological features defined on fat-suppressed T2 MRI images as areas of ill-delineated hyper signal intensities in comparison to unaffected areas(2) suggesting a change in material properties in the affected regions. Both bone volume fraction and mineral density within the lesion have been seen to alter(3). The aim of this study was to develop a finite element (FE) model of the knee joint to enable the mechanical effects of BMLs to be investigated. Method(s): FE models of a right human tibiofemoral joint were created from the Open Knee Generation 1 Specimen 1(4). Each model was manipulated in ScanIP (Synopsys-Simpleware, UK) to incorporate a BML. For this study, a spherical defect with 6mm radius was created in the tibia, initially centred 7mm below the surface of the bone beneath the contact region. Models were tested under a representative physiological load, and the effects of changes in the material properties and location of the defect on the contact pressure were investigated. Result(s): For the initial defect location, there was little change in the maximum contact pressure of the defect when the elastic modulus was halved or doubled (<2%). Changes in the location of the defect appeared to have a greater effect, influenced by distance below the bone surface and proximity to the centre of contact. Conclusion(s): A finite element model of the tibiofemoral joint was created with the ability to investigate the mechanical effect of size, location, and material properties of bone defects. Preliminary results indicate that the location of the defect is an important factor in governing the effect on the contact mechanics. The model provides the capability to more extensively examine the behaviour across the complex and varying shape of the joint.