Investigation of Mechanical, Material, and Compositional Determinants of Human Trabecular Bone Quality in Type 2 Diabetes

Context Increased bone fragility and reduced energy absorption to fracture associated with type 2 diabetes (T2D) cannot be explained by bone mineral density alone. This study, for the first time, reports on alterations in bone tissue’s material properties obtained from individuals with diabetes and known fragility fracture status. Objective To investigate the role of T2D in altering biomechanical, microstructural, and compositional properties of bone in individuals with fragility fracture. Methods Femoral head bone tissue specimens were collected from patients who underwent replacement surgery for fragility hip fracture. Trabecular bone quality parameters were compared in samples of 2 groups, nondiabetic (n = 40) and diabetic (n = 30), with a mean duration of disease 7.5 ± 2.8 years. Results No significant difference was observed in aBMD between the groups. Bone volume fraction (BV/TV) was lower in the diabetic group due to fewer and thinner trabeculae. The apparent-level toughness and postyield energy were lower in those with diabetes. Tissue-level (nanoindentation) modulus and hardness were lower in this group. Compositional differences in the diabetic group included lower mineral:matrix, wider mineral crystals, and bone collagen modifications—higher total fluorescent advanced glycation end-products (fAGEs), higher nonenzymatic cross-link ratio (NE-xLR), and altered secondary structure (amide bands). There was a strong inverse correlation between NE-xLR and postyield strain, fAGEs and postyield energy, and fAGEs and toughness. Conclusion The current study is novel in examining bone tissue in T2D following first hip fragility fracture. Our findings provide evidence of hyperglycemia’s detrimental effects on trabecular bone quality at multiple scales leading to lower energy absorption and toughness indicative of increased propensity to bone fragility.

Dental Cone Beam Computed Tomography for Trabecular Bone Quality Analysis in Maxilla and Mandible

The stability of a dental implant is one of the most important aspects that decide the success rate of implant treatment. The stability is considerably affected by the strength of trabecular bone present in maxilla and mandible. Thus, finding of trabecular bone strength is a key component for the success of dental implants. The trabecular bone strength is usually assessed by quantity of bone in terms of bone mineral density (BMD). Recently, it has been revealed that along with quantity of bone, strength of the bone also depends on quality features commonly referred as trabecular bone microarchitecture. Since the quality of the trabecular bone is varying across the maxilla and mandible, preoperative assessment of trabecular bone microarchitecture at sub-region of maxilla and mandible are essential for stable implant treatment. Thus, in this chapter, the authors inscribe the quantitative analysis of trabecular bone quality in maxilla and mandible using CBCT images by employing contourlet transform.

The Effects of Bone Microstructure on Subsidence Risk for ALIF, LLIF, PLIF, and TLIF Spine Cages

Several approaches (anterior, posterior, lateral, and transforaminal) are used in lumbar fusion surgery. However, it is unclear whether one of these approaches has the greatest subsidence risk as published clinical rates of cage subsidence vary widely (7–70%). Specifically, there is limited data on how a patient's endplate morphometry and trabecular bone quality influences cage subsidence risk. Therefore, this study compared subsidence (stiffness, maximum force, and work) between anterior (ALIF), lateral (LLIF), posterior (PLIF), and transforaminal (TLIF) lumbar interbody fusion cage designs to understand the impact of endplate and trabecular bone quality on subsidence. Forty-eight lumbar vertebrae were imaged with micro-ct to assess trabecular microarchitecture. micro-ct images of each vertebra were then imported into image processing software to measure endplate thickness (ET) and maximum endplate concavity depth (ECD). Generic ALIF, LLIF, PLIF, and TLIF cages made of polyether ether ketone were implanted on the superior endplates of all vertebrae and subsidence testing was performed. The results indicated that TLIF cages had significantly lower (p < 0.01) subsidence stiffness and maximum subsidence force compared to ALIF and LLIF cages. For all cage groups, trabecular bone volume fraction was better correlated with maximum subsidence force compared to ET and concavity depth. These findings highlight the importance of cage design (e.g., surface area), placement on the endplate, and trabecular bone quality on subsidence. These results may help surgeons during cage selection for lumbar fusion procedures to mitigate adverse events such as cage subsidence.

Dental Cone Beam Computed Tomography for Trabecular Bone Quality Analysis in Maxilla and Mandible

The stability of a dental implant is one of the most important aspects that decide the success rate of implant treatment. The stability is considerably affected by the strength of trabecular bone present in maxilla and mandible. Thus, finding of trabecular bone strength is a key component for the success of dental implants. The trabecular bone strength is usually assessed by quantity of bone in terms of bone mineral density (BMD). Recently, it has been revealed that along with quantity of bone, strength of the bone also depends on quality features commonly referred as trabecular bone microarchitecture. Since the quality of the trabecular bone is varying across the maxilla and mandible, preoperative assessment of trabecular bone microarchitecture at sub-region of maxilla and mandible are essential for stable implant treatment. Thus, in this chapter, the authors inscribe the quantitative analysis of trabecular bone quality in maxilla and mandible using CBCT images by employing contourlet transform.