The normal structure of human feet is optimized for shock dampening during walking and running. Foot binding was a historical practice in China aimed at restricting the growth of female feet for aesthetic reasons. In a bound foot the shock-dampening function normally facilitated by the foot arches is withdrawn, resulting in the foot functioning as a rigid extension of the lower leg. An interest...

Relaxation studies were conducted on specimens of bovine cancellous bone at post-yield strains. Stress and strain were measured for 1000s and the relaxation modulus was determined. Fifteen cylindrical, cancellous bone specimens were removed from one bovine femur in the anterior-posterior direction. The relaxation modulus was found to be a function of strain. Therefore cancellous bone is non-lin...

The objectives of this study were to determine the responses of cancellous bone in the distal tibial metaphysis (DTM), a low turnover, fatty (yellow) marrow site, to sham-aged, orchidectomy (ORX) and alfacalcidol treatment in sham-aged and ORX rats. Eighteen-month-old male sham and ORX rats were treated with 0.1 and 0.2 microg/kg alfacalcidol 5 days/wk p.o. for 12 weeks, double fluorescent labe...

Density is a salient property of bone and plays a crucial role in determining the mechanical properties of both its cancellous and cortical structural forms. Density is defined in a number of ways at either the bone tissue (D(app), apparent) or the bone material level (D(mat), material). The concept of density is relatively simple, but measuring it in the context of bone is a complex issue. The...

The sexual dimorphism in age-related loss of human vertebral cancellous bone is not fully understood and could be related to dimorphism in the bone cell populations. The objective of this study was to investigate age- and gender-related differences in the osteocyte population and its relationship with bone volume fraction for human vertebral cancellous bone. Histomorphometric techniques were us...

Electrostimulative fields are used to accelerate bone regeneration after fractures and to treat bone diseases. Most of these systems have upper and lower thresholds for electromagnetic fields, which have proven to have a positive effect towards bone growth. The biomechanical background, however, is still subject of ongoing research. Using numerical simulation, this paper investigates the field ...

PURPOSE/OBJECTIVE Prompted by preliminary findings, this study was conducted to investigate the impact of zoledronic acid on the cancellous bone microstructure and its effect on the level of β-catenin in a mouse model of postmenopausal osteoporosis. METHODS AND MATERIALS 96 8-week-old specific-pathogen-free C57BL/6 mice were randomly divided into 4 groups (24 per group): a sham group, an ovar...

Introduction Current methods for the assessment of fracture risk in osteoporosis are primarily based on bone mineral density (BMD) measurements. The mechanical properties of bones, however, are not only related to its density, but also to its internal architecture and its tissue properties. A non-invasive measurement of bone mechanical properties that accounts for the in-vivo bone internal arch...

Appropriate well-characterized bone defect animal models remain essential for preclinical research. This pilot study demonstrates a relevant animal model for cancellous bone defect healing. Three different defect diameters (8, 11, 14 mm) of fixed depth (25 mm) were compared in both skeletally immature (18-month-old) and aged sheep (5-year-old). In each animal, four defects were surgically creat...

An obvious means to improve the fixation of a cancellous bone screw is to augment the surrounding bone with cement. Previous studies have shown that bone augmentation with Calcium Phosphate (CaP) cement significantly improves screw fixation. Nevertheless, quantitative data about the optimal distribution of CaP cement is not available. The present study aims to show the effect of cement distribu...