Computational simulation of spontaneous bone straightening in growing children

Abstract

Periosteal surface pressures have been shown to inhibit bone formation and induce bone resorption, while tensile strains perpendicular to the periosteal surface have been shown to inhibit bone resorption and induce new bone deposition. A new computational model was developed to incorporate these experimental findings into simulations of spontaneous bone straightening in children with congenital posteromedial bowing of the tibia. Three-dimensional finite element models of the periosteum were used to determine the relationships between the defect angle and the distribution of bone surface pressures and strains due to growth-generated tensile strains in the periosteum. These relationships were incorporated into an iterative simulation to model development of a growing, bowed tibia with an initial defect angle of 27 degrees. When periosteal loads were included in the simulation, the defect angle decreased to 10 degrees after 2 years, and the bone straightened by an age of 25 years. When periosteal loads were not included in the simulation, the defect angle decreased to 23 degrees after 2 years, and a defect angle of 9 degrees remained at an age of 25 years. A "modeling drift" bone apposition/resorption pattern appeared only when periosteal loads were included. The results suggest that periosteal pressures and tensile strains induced by bone bowing can accelerate the process of bone straightening and lead to more complete correction of congenital bowing defects. Including the mechanobiological effects of periosteal surface loads in the simulations produced results similar to those seen clinically, with rapid straightening during the first few years of growth.

Tooth Eruption Results from Bone Remodelling Driven by Bite Forces Sensed by Soft Tissue Dental Follicles: A Finite Element Analysis

“…Orthodontic tooth movement is premised on resorption of the bony surface of the lamina dura where there is compression, coupled with bone deposition under tension [27], [81]. Remodelling of separate bony surfaces is similarly correlated with compression and tension [61], [62], so that our observation of overall compression covering crowns of erupting teeth, as well as of overall tension in soft tissues at apical sites, is consistent with our suggested mechanism for tooth eruption.…”

“…Compression of a bony surface adjacent to soft tissues results in resorption while bone is deposited on surfaces where there is tension [61], [62]. ‘Hydrostatic stress’ (alternatively hydrostatic strain) represents a measure to quantify the net compression or tension in each FE, by effectively averaging the stress components as per the following equation: Hydrostatic stress: , in which σ xx , σ yy , σ zz denotes the stress components along the three Cartesian axes respectively [60].…”

Computational modeling of bone density profiles in response to gait: a subject-specific approach

“…Finite element simulations can be used to predict bone growth and resorption in response to various different loading patterns that would not be feasible to study experimentally (Reina-Romo et al 2010;Weinans et al 1992). They also allow for efficient parameter studies, which can be used to identify key contributors to bone growth (Carpenter and Carter 2010a;Hambli et al 2011), bone straightening (Carpenter and Carter 2010b), bone torsion (Taylor et al 2008), or bone failure (Gitman et al 2010;Zhang et al 2010). Although promising, the use of finite element models to predict bone mineral density in osteoarthritis is still in its developmental stages, and the validation of the underlying models remains largely qualitative.…”

Ankle joint mechanics and foot proportions differ between human sprinters and non-sprinters

“…However, the authors found no differences in bone length between sedentary and exercised animals. Carpenter & Carter [44] used a computer model to simulate straightening of a congenitally bowed tibia in response to repeated loading. It is unknown, however, if human bone lengths or muscle moment arms adapt in similar ways in response to sport training.…”