Quantitative phenotyping of bone fracture repair: a review

Abstract

Fracture repair is a complex process that involves the interaction of numerous molecular factors, cell lineages and tissue types. These biological processes allow for an impressive feat of engineering: an elastic soft callus is progressively replaced by a more rigid and mineralized callus. During this reparative phase, the healing bone is exposed to a risk of re-fracture. Bone volume and bone quality are the two major factors determining the strength of the callus. Although both factors are important, often only bone volume is analyzed and reported in preclinical studies. Recent developments in techniques for examining bone quality in the callus will enable the rapid and detailed analysis of its material properties and its microstructure. This review aims to give an overview of the methods available for quantitatively phenotyping the bone callus in preclinical studies such as Raman spectroscopy, nanoindentation, scanning acoustic microscopy, in vivo micro-computed tomography (micro-CT) and high-resolution micro-CT. Consolidated and emerging experimental methods are described with a focus on their applicability, and with examples of their utilization.

The Role of Dot1l in Prenatal and Postnatal Murine Chondrocytes and Trabecular Bone

“…Dot1l loss in postnatal mouse chondrocytes also led to weakened trabecular bone. In particular, there was decrease in total trabecular bone (BV/TV) as well as changes in bone morphology (BS/BV), both of which are correlated with callus strength of healing fracture . In contrast, there was increased cortical bone thickness and decreased medullary space, which may be compensatory.…”

“…In particular, there was decrease in total trabecular bone (BV/TV) as well as changes in bone morphology (BS/BV), both of which are correlated with callus strength of healing fracture. (36) In contrast, there was increased cortical bone thickness and decreased medullary space, which may be compensatory. The trabecular bone loss was consistent with a recent study of DOT1L-inhibitor treatment of ovariectomized mice, (18) and increasing DOT1L activity may be therapeutic in human osteoporosis, particularly in postmenopausal women.…”

Structural and Qualitative Bone Remodeling Around Repetitive Loaded Implants in Rabbits

“…Most conventional studies in implant dentistry have focused on the evaluation of bone‐to‐implant contact and bone formation around dental implants regardless of mechanical loading. However, recent medical reports and basic researches have emphasized that both evaluation of BMD and bone quality are ultimately required to completely account for bone strength as related to bone mechanical function . BMD and bone quality account for approximately 70% and 30% of bone strength, respectively .…”

“…However, recent medical reports and basic researches have emphasized that both evaluation of BMD and bone quality are ultimately required to completely account for bone strength as related to bone mechanical function. 37,38 BMD and bone quality account for approximately 70% and 30% of bone strength, respectively. 4,39 Moreover, bone architecture, which reflects osteocyte numbers and the preferential alignment direction and degree of BAp c-axis/collagen fibers, is one of the critical factors in determining bone quality.…”

In Vitro and In Vivo Study of Titanium Grade IV and Titanium Grade V Implants with Different Surface Treatments

“…Trabecular bone microarchitecture is calculated by a plugin based on Bob Dougherty's Local Thickness Plugin, which assesses the mean and the standard deviation directly from the pixel values in the resulting thickness map. These parameters are used as predictors for the resistance to fracture and the healing process [31,32]. -Bone Volume, Total Volume, and the Bone Volume Fraction (BV/TV).…”