Micro-scale assessment of bone quality changes in adult cadaveric men with congestive hepatopathy

Bone quality analysis of the mandible in alcoholic liver cirrhosis: Anatomical, microstructural, and microhardness evaluation

OBJECTIVES

Alcoholic bone disease has been recognized in contemporary literature as a systemic effect of chronic ethanol consumption. However, evidence about the specific influence of alcoholic liver cirrhosis (ALC) on mandible bone quality is scarce. The aim of this study was to explore microstructural, compositional, cellular, and mechanical properties of the mandible in ALC individuals compared with a healthy control group.

MATERIALS AND METHODS

Mandible bone cores of mаle individuаls with ALC (n = 6; age: 70.8 ± 2.5 yeаrs) and age-matched healthy controls (n = 11; age: 71.5 ± 3.8 yeаrs) were obtаined postmortem during аutopsy from the edentulous аlveolаr bone in the mandibular first molаr region аnd the mаndibulаr аngulus region of each individual. Micro-computed tomogrаphy wаs used to аssess bone microstructure. Analyses based on quаntitаtive bаckscаttered electron microscopy included the characterization of osteon morphology, osteocyte lаcunаr properties, and bone mаtrix minerаlizаtion. Composition of bone minerаl аnd collаgen phаses was assessed by Rаmаn spectroscopy. Histomorphometry wаs used to determine cellulаr аnd tissue chаrаcteristics of bone specimens. Vickers microhardness test was used to evaluate cortical bone mechanical properties.

RESULTS

The ALC group showed higher closed cortical porosity (volume of pores thаt do not communicаte with the sаmple surfаce) (p = 0.003) and smaller lacunar area in the trabecular bone of the molar region (p = 0.002) compared with the Control group. The trabecular bone of the angulus region showed lower osteoclast number (p = 0.032) in the ALC group. There were higher carbonate content in the buccal cortex of the molar region (p = 0.008) and lower calcium content in the trabecular bone of the angulus region (p = 0.042) in the ALC group. The cortical bone showed inferior mechanical properties in the ALC cortical bony sites (p < 0.001), except for the buccal cortex of the molar region (p = 0.063). There was no significant difference in cortical thickness between the groups.

CONCLUSIONS

Bone quality is differentially altered in ALC in two bony sites and compartments of the mandible, which leads to impaired mechanical properties.

CLINICAL RELEVANCE

Altered mandible bone tissue characteristics in patients with ALC should be considered by dental medicine professionals prior to oral interventions in these patients. Knowledge about mandible bone quality alterations in ALC is valuable for determining diagnosis, treatment plan, indications for oral rehabilitation procedures, and follow-up procedures for this group of patients.

Micro-scale vertebral features in postmenopausal women with alcohol-associated and metabolic-associated fatty liver disease: ex vivo bone quality analyses

PURPOSE

Although epidemiological studies indicate increased fracture risk in women with alcohol-associated liver disease (AALD) and metabolic-associated fatty liver disease (MAFLD), data about their micro-scale bone features are still limited. We aimed to characterize bone quality changes in the anterior mid-transverse part of the first lumbar vertebral body collected from 32 adult postmenopausal females. Based on pathohistological assessment of the liver tissue, individuals were divided into AALD (n = 13), MAFLD (n = 9), and control group (n = 10).

METHODS

We analyzed trabecular and cortical micro-architecture (using micro-computed tomography), bone mechanical properties (using Vickers microhardness tester), osteocyte lacunar network and bone marrow adiposity morphology (using optic microscopy). Data were adjusted to elude the covariant effects of advanced age and body mass index on our results.

RESULTS

Our data indicated a minor trend toward deteriorated bone quality in MAFLD women, presented in impaired trabecular and cortical micro-architectural integrity, which could be associated with bone marrow adiposity alterations noted in these women. Additionally, we observed a significant decline in micro-architectural, mechanical, and osteocyte lacunar features in lumbar vertebrae collected from the AALD group. Lastly, our data indicated that vertebral bone deterioration was more prominent in the AALD group than in the MAFLD group.

CONCLUSION

Our data suggested that MAFLD and AALD are factors that could play a part in compromised vertebral strength of postmenopausal women. Also, our data contribute to understanding the multifactorial nature of bone fragility in these patients and highlight the necessity for developing more effective patient-specific diagnostic, preventive, and therapeutic strategies.

Bone loss in chronic liver diseases: Could healthy liver be a requirement for good bone health?

Given that the liver is involved in many metabolic mechanisms, it is not surprising that chronic liver disease (CLD) could have numerous complications. Secondary osteoporosis and increased bone fragility are frequently overlooked complications in CLD patients. Previous studies implied that up to one-third of these individuals meet diagnostic criteria for osteopenia or osteoporosis. Recent publications indicated that CLD-induced bone fragility depends on the etiology, duration, and stage of liver disease. Therefore, the increased fracture risk in CLD patients puts a severe socioeconomic burden on the health system and urgently requires more effective prevention, diagnosis, and treatment measures. The pathogenesis of CLD-induced bone loss is multifactorial and still insufficiently understood, especially considering the relative impact of increased bone resorption and reduced bone formation in these individuals. It is essential to note that inconsistent findings regarding bone mineral density measurement were previously reported in these individuals. Bone mineral density is widely used as the "golden standard" in the clinical assessment of bone fragility although it is not adequate to predict individual fracture risk. Therefore, microscale bone alterations (bone microstructure, mechanical properties, and cellular indices) were analyzed in CLD individuals. These studies further support the thesis that bone strength could be compromised in CLD individuals, implying that an individualized approach to fracture risk assessment and subsequent therapy is necessary for CLD patients. However, more well-designed studies are required to solve the bone fragility puzzle in CLD patients.