High-impact exercise stimulated localised adaptation of microarchitecture across distal tibia in postmenopausal women

Abstract

We provided evidence that a 6-month regular hopping exercise intervention can increase trabecular number and possibly trabecular volume fraction of the distal tibia. Our novel localised analysis demonstrated region-specific changes, predominantly in the anterior region, in postmenopausal women.

The plate-to-rod transition in trabecular bone loss is elusive

“…Ellipsoid factor (EF) has been proposed as an alternative method to measure the plate-to-rod transition in trabecular bone [15]. EF has since been used within and beyond bone biology, for example in bone surgical implant testing [16] and the characterization of the trabecular bone phenotype of genetic dwarfism [17], of the primate mandible [18], of the human tibia [19], of animal models of osteoarthritis [20], and fuel cell performance [21,22]. Apart from the original critique of SMI [14], as far as we know, there have been no further reports of EF in osteoporotic samples in the literature.…”

Remodelling of trabecular bone in human distal tibia: A model based on an in-vivo HR-pQCT study

“…Participants who agreed to take part in the 6-month follow-up visit gave a written informed consent before participation. HR-pQCT (XtremeCT, Scanco Medical AG, Bruttisellen, Switzerland) scans of distal tibia were scheduled according to the manufacturer's standard protocol (60 kVp, 1000 mA, 100-msintegration time) at Month 0 and Month 6 [4] [28]. Prior to image acquisition, the tibia was lifted to a horizontal position, perpendicular to the gantry of the scanner to ensure the correct position upon entry.…”

“…Nine cubic volumes of interest (VOIs) with a side length of 4 mm were extracted digitally from the trabecular region of distal tibia from nine participants. A 3D registration protocol, the same as in the previous publication [27] was used to ensure that VOIs from the same position were extracted from both the baseline and follow-up scans [4]. Briefly, a two-step registration was performed: first, the centres of mass were pre-aligned between two images; second, the pre-aligned follow-up image was registered to the baseline image based on a normalized mutual information metric and resampled using a Lanczos interpolator.…”

“…At the distal tibia, trabecular compartment carries up to 71% of the axial load and is actively remodelled to adapt its microstructure and mechanical properties due to habitual loading [3]. In addition, a recent study by Du et al [4] suggests that exercise can alter the characteristics of the trabecular-bone adaptation process in postmenopausal women, highlighting the importance of introducing an in-vivo human model in the study of trabecular-bone remodelling. However, our understanding on the mechanisms, which drive the remodelling of human trabecular bone is still incomplete.…”

Mechanical Stimuli in Prediction of Trabecular Bone Adaptation: Numerical Comparison

“…It was found that intensive mechanical stimulation results in thicker and mechanically stronger bones and bone morphology with individual elements of this bone tissue, trabeculae, aligned along the loading direction [1]. In contrast, a lack of mechanostimulation induces a bonemass reduction, thinning of trabeculae, and deterioration of mechanical properties [2]. Loadinduced adaptation is implemented through resorption of old and fractured bone and formation of a new bone material.…”