Finite element studies of some juxtarticular stress changes due to localized subchondral stiffening

doi:10.1016/0021-9290(84)90075-7

Journal of Biomechanics

Volume 17, Issue 1, 1984, Pages 11-21, 23-24

https://doi.org/10.1016/0021-9290(84)90075-7 Get rights and content

Abstract

A finite element analysis was undertaken in concert with an animal model of mechanically-induced osteoarthritis. The numerical model was used to explore stress transmission anomalies associated with localized subchondral stiffening due to implantation of small cylindrical plugs immediately below the subchondral plate of sheep. The quasi-static, plane strain computational formulation included solution of the non-linear intra-articular contact problem, and was validated by comparison with a corresponding analytical solution and with the in vivo experimental results.

The numerical results showed that stress aberrations due to metal implant insertion were felt most greatly in the bone immediately surrounding the implant, but that nominal compressive stress elevations up to about 50% could also be induced in the overlying deep hyaline cartilage layer. This localized cartilage stress elevation following the insertion of a metal plug could be seriously affected by a number of factors, including the positioning of the implant, variation in the area of intra-articular contact, or the elastic modulus of the cancellous bone and/or subchondral plate. Experimentally-observed fibrous encapsulation also reduced the cartilage stress elevation effect, but later bony remodelling and the development of a corticalized shell around the implant encapsulation served to re-elevate the local cartilage stresses.

References (20)

T.D. Brown et al.
In vitro contact stress distributions in the natural human hip
J. Biomechanics
(1983)
I.L. Paul et al.
Musculo-skeletal shock absorption: relative contribution of bone and soft tissues at various frequencies
J. Biomechanics
(1978)
E.L. Radin et al.
Response of joints to impact loading. III relationship between trabecular microfractures and cartilage degeneration
J. Biomechanics
(1973)
A.M. Ahmed et al.
In vitro measurement of pressure distribution at articular interfaces of synovial joints
N.M. Belajef
Memoirs on Theory of Structures, St. Petersburg
T.D. Brown et al.
The apparent elastic modulus of juxtarticular subchondral bone of the femoral head
D.R. Carter et al.
The compressive behavior of bone as a two-phase porous structure
J. Bone Jt Surg.
(1977)
S. Devel et al.
Joint changes after overuse and peak overloading of rabbit knees in vivo
Acta orthop. scand.
(1978)
F.C. Ewald et al.
Hip cartilage supported by methacrylate in canine arthroplasty
Clin. Orthop.
(1982)
T. Fukubayashi et al.
The contact area and pressure distribution pattern of the knee—a study of normal and osteoarthritic knee joints
Acta orthop. scand.
(1980)

There are more references available in the full text version of this article.

Cited by (125)

High-Resolution Peripheral Quantitative Computed Tomography in Rheumatic Diseases: A New Option for Knee Osteoarthritis
2024, Radiologic Clinics of North America
Three-dimensional finite element modeling of human knee joint
2023, Cartilage Tissue and Knee Joint Biomechanics: Fundamentals, Characterization and Modelling
Patient-specific finite element (FE) models of human knee joint have been extensively developed to understand the contact mechanics of the joint. For simplicity, the tissues are widely considered as elastic solids, even fluid pressurization in cartilage and meniscus is essential for the load sharing and redistribution in the joint and the homeostasis of the tissues. Recent development in constitutive modeling yet needs to be implemented in joint modeling. Fibril reinforcement and fluid pressure were introduced in three-dimensional knee joint models in the last decade. The time-dependent response of the joint, including creep and relaxation of the joint produced by the soft tissues, can be now determined within a reasonable time using high-performance computing. The in vivo creep response of human knee joint can be even measured with advanced medical imaging to validate the FE model. Concerns remain pertaining the reliability of constructed joint geometry and FE solutions, which may be resolved with advances in imaging, imaging processing, and new algorithms in the FE solvers. Future patient-specific knee models may combine stress/strain analysis and simulation of mechanobiology, which can then be used to understand and possibly predict, for example, the onset of knee osteoarthritis or the outcome of physiotherapy.
Contribution of joint tissue properties to load-induced osteoarthritis
2022, Bone Reports
Clinical evidence suggests that abnormal mechanical forces play a major role in the initiation and progression of osteoarthritis (OA). However, few studies have examined the mechanical environment that leads to disease. Thus, using a mouse tibial loading model, we quantified the cartilage contact stresses and examined the effects of altering tissue material properties on joint stresses during loading.
Using a discrete element model (DEA) in conjunction with joint kinematics data from a murine knee joint compression model, the magnitude and distribution of contact stresses in the tibial cartilage during joint loading were quantified at levels ranging from 0 to 9 N in 1 N increments. In addition, a simplified finite element (FEA) contact model was developed to simulate the knee joint, and parametric analyses were conducted to investigate the effects of altering bone and cartilage material properties on joint stresses during compressive loading.
As loading increased, the peak contact pressures were sufficient to induce fibrillations on the cartilage surfaces. The computed areas of peak contact pressures correlated with experimentally defined areas of highest cartilage damage. Only alterations in cartilage properties and geometry caused large changes in cartilage contact pressures. However, changes in both bone and cartilage material properties resulted in significant changes in stresses induced in the bone during compressive loading.
The level of mechanical stress induced by compressive tibial loading directly correlated with areas of biological change observed in the mouse knee joint. These results, taken together with the parametric analyses, are the first to demonstrate both experimentally and computationally that the tibial loading model is a useful preclinical platform with which to predict and study the effects of modulating bone and/or cartilage properties on attenuating OA progression. Given the direct correlation between computational modeling and experimental results, the effects of tissue-modifying treatments may be predicted prior to in vivo experimentation, allowing for novel therapeutics to be developed.
Relationships between cartilage thickness and subchondral bone mineral density in non-osteoarthritic and severely osteoarthritic knees: In vivo concomitant 3D analysis using CT arthrography
2019, Osteoarthritis and Cartilage
Citation Excerpt :
Then, an sBMD value was calculated for each subchondral point of the 3D femur models by averaging the CT intensity in the first 3 mm of bone17,19. A penetration of 3 mm was selected to strictly measure the BMD of the subchondral bone17,38,39. A CTh value was also determined for each subchondral point of the 3D femur models by calculating the distance to the articular surface of the 3D cartilage models36,40.
To test whether subchondral bone mineral density (sBMD) and cartilage thickness (CTh) of femoral condyles are correlated in knees without and with severe medial femorotibial osteoarthritis (OA), using a subregional analysis with computerized tomography (CT) arthrography.
CT arthrograms of 50 non-OA (18 males, 58.7 (interquartile range (IQR) = 6.6 years)) and 50 severe medial OA (24 males, 60.5 (IQR = 10.7) years) knees, were retrospectively analyzed. Bone and cartilage were segmented using custom-designed software, leading to 3D models on which each point of the subchondral surface is given a CTh and sBMD value. The average sBMD and CTh were then calculated for the entire weight-bearing regions as well as specific subregions of interest. Linear bivariate and multivariable analyses were performed to test for relationships between sBMD and CTh (regional and subregional measures, or medial-to-lateral ratios), with confounders of age, gender, femoral bone size and femorotibial angle.
In non-OA knees, the sBMD and CTh medial-to-lateral ratios were positively correlated for the total region and the external and internal subregions (r ≥ 0.341, P ≤ 0.015). In OA knees, sBMD and CTh medial-to-lateral ratios were negatively correlated for the total region and the external and central subregions (r ≤ −0.538, P < 0.001). Additional positive/negative relationships in the non-OA/OA knees were observed between sBMD and CTh measures in the medial compartment.
The positive correlation between sBMD and CTh in non-OA knees, and the negative one in OA knees, bring support to the theory of a subchondral bone/cartilage functional unit, which could help to better understand the pathophysiology of OA.
Shock absorbing ability in healthy and damaged cartilage-bone under high-rate compression
2019, Journal of the Mechanical Behavior of Biomedical Materials
Articular cartilage is a soft tissue that distributes the loads in joints and transfers the compressive load to the underlying bone. At high rate and magnitudes of mechanical loading, cartilage and subchondral bone together are susceptible to damage. In addition, any disruption to the cartilage's structure, caused by injury, trauma or disorder such as osteoarthritis (OA), can alter the mechanism of load transfer from the cartilage to the underlying bone. Changes in the cartilage structure can also alter the ability of cartilage-bone to absorb and dissipate the impact energy. To investigate the effects of cartilage degradation on cartilage-bone shock absorption ability, the top 50% of the cartilage thickness was removed (modified cartilage) to mimic the cartilage thickness reduction in Grade III cartilage lesion and the remaining cartilage-bone unit (modified cartilage-bone) was compressed at high-rate (4% strain at 5 Hz). High-speed camera and microscope were used to capture microscopic deformation, and digital image correlation technique (DIC) employed to quantify the deformation of cartilage and bone. The mechanical properties (i.e. stiffness, strain, absorbed and dissipated energies) of cartilage and bone were calculated before and after the removal of the top 50% of the cartilage thickness, consisting of both the superficial tangential zone (STZ) and part of the middle zone of the cartilage. The results showed a significant degradation in the mechanical properties of the cartilage-bone unit after the removal of the top 50% cartilage thickness. The stiffness of the modified cartilage reduced significantly (by ~39%) and energy absorption in underlying bone increased by 32%, which can make the bone more vulnerable to damage in the modified cartilage-bone unit. In addition, the energy dissipation in the modified cartilage-bone unit was also increased by approximately 14%. These changes in mechanical properties suggest a crucial role of the STZ and middle zone (within the top 50% cartilage thickness) in protecting the underlying bone from the severe compressive impact loading. Results also indicated that under physiological contact stress of 7 MPa, strain in damaged cartilage was increased by 3.22% without affecting the mechanical behaviour of the underlying bone.
Role of subchondral bone properties and changes in development of load-induced osteoarthritis in mice
2017, Osteoarthritis and Cartilage
Citation Excerpt :
Given the clinical evidence of SCB thickening in OA patients, historically, the hypothesis has been that disease initiation is associated with increased mass and apparent stiffening of the SCB plate, diminishing its ability to act as an effective shock absorber for the cartilage8–10. However, recent studies suggest that SCB stiffening may not influence the stresses engendered on the cartilage surface3,11 leading to the conclusion that OA joint pathology initiates in the articular cartilage rather than the SCB. In more advanced stages of OA, abnormal mechanical forces can contribute to articular cartilage loss via the initiation of microcracks in the SCB plate that activate a bone remodeling response, leading to tidemark advancement and subsequent thinning of the cartilage3,12–14.
Animal models recapitulating post-traumatic osteoarthritis (OA) suggest that subchondral bone (SCB) properties and remodeling may play major roles in disease initiation and progression. Thus, we investigated the role of SCB properties and its effects on load-induced OA progression by applying a tibial loading model on two distinct mouse strains treated with alendronate (ALN).
Cyclic compression was applied to the left tibia of 26-week-old male C57Bl/6 (B6, low bone mass) and FVB (high bone mass) mice. Mice were treated with ALN (26 μg/kg/day) or vehicle (VEH) for loading durations of 1, 2, or 6 weeks. Changes in articular cartilage and subchondral and epiphyseal cancellous bone were analyzed using histology and microcomputed tomography.
FVB mice exhibited thicker cartilage, a thicker SCB plate, and higher epiphyseal cancellous bone mass and tissue mineral density than B6 mice. Loading induced cartilage pathology, osteophyte formation, and SCB changes; however, lower initial SCB mass and stiffness in B6 mice did not attenuate load-induced OA severity compared to FVB mice. By contrast, FVB mice exhibited less cartilage damage, and slower-growing and less mature osteophytes. In B6 mice, inhibiting bone remodeling via ALN treatment exacerbated cartilage pathology after 6 weeks of loading, while in FVB mice, inhibiting bone remodeling protected limbs from load-induced cartilage loss.
Intrinsically lower SCB properties were not associated with attenuated load-induced cartilage loss. However, inhibiting bone remodeling produced differential patterns of OA pathology in animals with low compared to high SCB properties, indicating that these factors do influence load-induced OA progression.

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^∗: Current address: Department of Orthopaedic Surgery, University of Iowa Hospitals and Clinics, Iowa City, IA 52242, U.S.A.

^†: Department of Orthopaedic Surgery, West Virginia University, Morgantown, WV 26506, U.S.A.

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Journal of Biomechanics

Abstract

References (20)

In vitro contact stress distributions in the natural human hip

J. Biomechanics

Musculo-skeletal shock absorption: relative contribution of bone and soft tissues at various frequencies

J. Biomechanics

Response of joints to impact loading. III relationship between trabecular microfractures and cartilage degeneration

J. Biomechanics

In vitro measurement of pressure distribution at articular interfaces of synovial joints

Memoirs on Theory of Structures, St. Petersburg

The apparent elastic modulus of juxtarticular subchondral bone of the femoral head

The compressive behavior of bone as a two-phase porous structure

J. Bone Jt Surg.

Joint changes after overuse and peak overloading of rabbit knees in vivo

Acta orthop. scand.

Hip cartilage supported by methacrylate in canine arthroplasty

Clin. Orthop.

The contact area and pressure distribution pattern of the knee—a study of normal and osteoarthritic knee joints

Acta orthop. scand.

Cited by (125)

High-Resolution Peripheral Quantitative Computed Tomography in Rheumatic Diseases: A New Option for Knee Osteoarthritis

Three-dimensional finite element modeling of human knee joint

Contribution of joint tissue properties to load-induced osteoarthritis

Relationships between cartilage thickness and subchondral bone mineral density in non-osteoarthritic and severely osteoarthritic knees: In vivo concomitant 3D analysis using CT arthrography

Shock absorbing ability in healthy and damaged cartilage-bone under high-rate compression

Role of subchondral bone properties and changes in development of load-induced osteoarthritis in mice