Abstract
Abstract
Objectives
Over 1% of the global population suffers with ankle osteoarthritis (OA), yet there is limited knowledge on the changes to subchondral bone with OA. In other joints, it has been shown that bone becomes osteosclerotic, with fewer, thicker trabeculae that become hypomineralised, causing an increased apparent bone volume fraction (BV/TV). Microstructural alterations reduce overall joint strength, which may impact the success of late-stage surgical interventions, such as total ankle arthroplasty (TAA). Previous ankle studies have evaluated changes to cartilage, bone plate and bone morphology with OA, hence this study aimed to characterise changes to trabecular architecture.
Methods
Three ankle joints were isolated from non-diseased cadaveric feet (three males: 43, 50 and 57 years, MEEC 18-027). Cylindrical subchondral bone specimens (N=6, 6.5 mm Ø) were extracted from the tibial plafond. Osteoarthritic bone samples (N=6, distal tibia) were sourced from local patients (three males: 65, 58 and 68 years, NREC 07/Q1205/27) undergoing TAA surgery. Specimens were imaged using µCT at a 16 µm isotropic resolution (µCT-100 ScanCo Medical). Virtual cores of bone (6.5 mm Ø) were extracted from the image data of the osteoarthritic specimens and trimmed to a height of 4 mm. BoneJ was used to evaluate key morphological indices: BV/TV; anisotropy (DA); trabecular thickness (Tb.Th); trabecular density (Conn.D) and ellipsoid factor (EF) which characterises rod/plate geometry. Differences between the two groups of specimens were evaluated using a t-test with Bonferroni correction.
Results
Significant increases in BV/TV and Tb.Th (p<0.01) were observed with OA compared to non-diseased. Differences in EF showed a shift to more rod-dominated structure with OA, but this was not significant. No significant differences to DA and Conn.D were observed.
Conclusions
The results of this study agree with trends observed in other OA joints, but would benefit from a larger sample size.
Declaration of Interest
(b) declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research reported:I declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.
