Abstract
BackgroundBone can adjust its morphological structure to adapt to the changes of mechanical environment, i.e. the bone structure change is related to mechanical loading. This implies that osteoarthritis may be closely associated with knee joint deformity. The purposes of this paper were to simulate the internal bone mineral density (BMD) change in three-dimensional (3D) proximal tibia under different mechanical environments, as well as to explore the relationship between mechanical environment and bone morphological abnormity.MethodsThe right proximal tibia was scanned with CT to reconstruct a 3D proximal tibia model in MIMICS, then it was imported to finite element software ANSYS to establish 3D finite element model. The internal structure of 3D proximal tibia of young normal people was simulated using quantitative bone remodeling theory in combination with finite element method, then based on the changing pattern of joint contact force on the tibial plateau in valgus knees, the mechanical loading was changed, and the simulated normal tibia structure was used as initial structure to simulate the internal structure of 3D proximal tibia for old people with 6° valgus deformity. Four regions of interest (ROIs) were selected in the proximal tibia to quantitatively analyze BMD and compare with the clinical measurements.ResultsThe simulation results showed that the BMD distribution in 3D proximal tibia was consistent with clinical measurements in normal knees and that in valgus knees was consistent with the measurement of patients with osteoarthritis in clinics.ConclusionsIt is shown that the change of mechanical environment is the main cause for the change of subchondral bone structure, and being under abnormal mechanical environment for a long time may lead to osteoarthritis. Besides, the simulation method adopted in this paper can more accurately simulate the internal structure of 3D proximal tibia under different mechanical environments. It helps to better understand the mechanism of osteoarthritis and provides theoretical basis and computational method for the prevention and treatment of osteoarthritis. It can also serve as basis for further study on periprosthetic BMD changes after total knee arthroplasty, and provide a theoretical basis for optimization design of prosthesis.
Highlights
Bone can adjust its morphological structure to adapt to the changes of mechanical environment, i.e. the bone structure change is related to mechanical loading
The simulated normal proximal tibia structure of young people is similar with the real proximal tibia structure (Figure 3), which can be seen from the following three aspects: (1) Seen from Figure 4a-c, there is a layer of cortical bone covering the whole tibia, and the cortical bone is relatively continuous and completed, This is consistent with the real proximal tibial cortical bone structure in Figure 3; (2) From Figure 4d it can be seen that there is medullary cavity within distal tibia, This characteristic is consistent with the real proximal tibial structure in Figure 3; (3) Beneath the tibial plateau there is cancellous bone, and the bone mineral density (BMD) in medial region is bigger than that in lateral region
From the simulation results of proximal tibia of young normal people it can be seen that the average BMDs in ROI1 and ROI2 are 1.23 g/cm3 and 1.03 g/cm3, and the M:L BMD Ratio is 1.19
Summary
Bone can adjust its morphological structure to adapt to the changes of mechanical environment, i.e. the bone structure change is related to mechanical loading. This implies that osteoarthritis may be closely associated with knee joint deformity. The typical radiographic features of knee osteoarthritis include degeneration of cartilage, subchondral bone sclerosis and osteophyte formation. It is thought that subchondral bone changes after cartilage degenerates, so much attention is paid to the change of cartilage and the treatment of osteoarthritis. The subchondral bone changes in the early stage of osteoarthritis and leads to the degeneration of articular cartilage, which may be the initial cause of osteoarthritis [2,3]. It is important to investigate the roles of subchondral bone for the prevention and treatment of osteoarthritis
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
