The effect of ageing and osteoarthritis on the mechanical properties of cartilage and bone in the human knee joint

Abstract

Osteoarthritis is traditionally associated with cartilage degeneration although is now widely accepted as a whole-joint disease affecting the entire osteochondral unit; however site-specific cartilage and bone material properties during healthy ageing and disease are absent limiting our understanding. Cadaveric specimens (n = 12; 31–88 years) with grades 0–4 osteoarthritis, were dissected and spatially correlated cartilage, subchondral and trabecular bone samples (n = 8 per cadaver) were harvested from femoral and tibial localities. Nanoindentation was utilised to obtain cartilage shear modulus (G′) and bone elastic modulus (E). Cartilage G′ is strongly correlated to age (p = 0.003) and osteoarthritis grade (p = 0.007). Subchondral bone E is moderately correlated to age (p = 0.072) and strongly correlated to osteoarthritis grade (p = 0.013). Trabecular bone E showed no correlation to age (p = 0.372) or osteoarthritis grade (p = 0.778). Changes to cartilage G′ was significantly correlated to changes in subchondral bone E (p = 0.007). Results showed preferential medial osteoarthritis development and moderate correlations between cartilage G′ and sample location (p = 0.083). Also demonstrated for the first time was significant correlations between site-matched cartilage and subchondral bone material property changes during progressive ageing and osteoarthritis, supporting the role of bone in disease initiation and progression. This clinically relevant data indicates a causative link with osteoarthritis and medial habitual loading.

Tibial subchondral trabecular bone micromechanical and microarchitectural properties are affected by alignment and osteoarthritis stage

“…Investigating the BMI effect on BV/TV, we found a weak and non-significant relationship between BV.TV and BMI for medial samples, whereas Reina et al found a moderately significant relationship 32 . Like the Peters et al study, we found no link between BMI and tissue elastic modulus 30 . These findings suggest that BMI should not have a major effect on STB tissue elastic modulus.…”

“…Peters et al found no difference in trabecular bone elastic tissue modulus at different stages in the disease 30 . However their subjects presented less severe OA and their samples were tested dehydrated.…”

Characterisation and in vitro and in vivo evaluation of supercritical-CO2-foamed β-TCP/PLCL composites for bone applications

“…The modulus of the composite was more similar to the modulus of cartilage (2.4-10 MPa) (Beck et al, 2016) than to that of trabecular bone (10.75-13.66 GPa) (Peters et al, 2018), thus mimicking the soft callus formed during natural bone healing. Therefore, a bone defect treated with this composite would still require additional fixation to restrain the defect site.…”

Mechanical Heterogeneity in the Bone Microenvironment as Characterised by Atomic Force Microscopy

“…Tensile tests on whole bones reported in 1976, showed only moderate differences between bones from humans at different ages (54). Recently, micro-/nano-indentation tests revealed that the mechanical properties of human cortical (55) and trabecular (56) bones were remarkably constant as a function of age. The elastic modulus of murine growth plate are reported to be significantly different between the embryonic stage and postnatal stage, age 2 week, but did not vary significantly through the next growth stages until adulthood (up to age 4 months) (25).…”