Role of trabecular morphology in the etiology of age-related vertebral fractures

Abstract

Osteoporotic compression fractures of the spine differ from most other age-related fractures in that they usually are associated with minimal trauma and with loads no greater than those encountered during normal activities of daily living. With aging and osteoporosis, there is progressive resorption of bone, resulting in reductions in bone density, thinning of trabeculae, and loss of trabecular contiguity. These changes in trabecular bone structure are associated with losses in bone strength which are disproportionate to the reductions in bone mass alone. To explain this disproportionate loss of bone strength, the prevailing opinion is that density reductions in the vertebral centrum are accompanied by a reduction in the number of trabeculae, by preferential resorption of horizontal trabeculae, and by hypertrophy of the remaining vertical trabeculae. To evaluate this view of vertebral morphology, we performed three-dimensional stereological analysis of trabecular bone extracted from midsagittal sections of first lumbar vertebral bodies from 12 donors spanning an age of 27-81 years. We found that both the number (R2 = 0.63, P < 0.01) and thickness (R2 = 0.91, P < 0.01) of trabeculae decreased linearly with density (as expressed by bone volume fraction) whereas the spacing between the trabeculae (R2 = 0.61, P < 0.01) increased reciprocally. There were more vertical trabeculae with transverse trabeculae at all densities, and the number of vertical trabeculae changed with density at twice the rate of the number of transverse trabeculae (P < 0.001). These data do not support the prevailing view that there is preferential resorption of horizontal trabeculae or hypertrophy of the remaining vertical trabeculae.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone loss dynamics result in trabecular alignment in aging and ovariectomized rats

“…4,[32][33][34] In the baseline measurement at week 0 of this study, we observed the same relation. However, our longitudinal data showed an opposite relation: Trabecular thickness increased when bone was lost (Fig.…”

Increased femoral neck cancellous bone and connectivity in coxarthrosis (hip osteoarthritis)

“…Increased trabecular width in both genders would also increase the strength in the femoral neck; a recent study in rats found a significant correlation between trabecular thickness and bone strength at the femoral neck [41]. Additionally, buckling theory argues that the buckling load of a columnar structure, such as a trabecula, is related to the ratio of trabecular thickness to effective length [40]. In the femoral neck, although a greater proportion of strength is derived from the cortex, an important role of cancellous bone is widely thought to be its capacity to buttress the cortex internally and prevent cortical buckling under excessive compression, for example, during a sideways fall on the trochanter [30].…”

Multiscale modelling and nonlinear finite element analysis as clinical tools for the assessment of fracture risk

“…For example, in osteopenic patients, these changes include a decrease in trabecular number, a decrease in trabecular thickness and an increase in trabecular spacing. The consequence is a structure more prone to buckling (Snyder et al 1993), further necessitating the use of nonlinear FE simulations. Drugs preventing bone loss not only affect formation and resorption rates, but also its tissue properties and the quality of the microarchitecture.…”