Journal
JOURNAL OF BONE AND MINERAL RESEARCH
Volume 33, Issue 4, Pages 606-620Publisher
WILEY
DOI: 10.1002/jbmr.3354
Keywords
CORTICAL BONE; CORTICAL POROSITY; BONE REMODELING; BONE RESORPTION; BONE FORMATION; AGING; COUPLING
Categories
Funding
- Velux Foundation [VELUX34368]
- Danish Southern Region Research Grant [15/24851]
Ask authors/readers for more resources
Intracortical bone remodeling normally ensures maintenance of the cortical bone matrix and strength, but during aging, this remodeling generates excessive porosity. The mechanism behind the age-induced cortical porosity is poorly understood and addressed in the present study. This study consists of a histomorphometric analysis of sections of iliac bone specimens from 35 women (age 16-78 years). First, the study shows that the age-induced cortical porosity reflects an increased pore size rather than an increased pore density. Second, it establishes a novel histomorphometric classification of the pores, which is based on the characteristics of the remodeling sites to which each pore is associated. It takes into consideration (i) the stage of the remodeling event at the level where the pore is sectioned, (ii) whether the event corresponds with the generation of a new pore through penetrative tunneling (type 1 pores) or with remodeling of an existing pore (type 2 pores), and (iii) in the latter case, whether or not the new remodeling event leads to the coalescence of pores. Of note, the advantage of this classification is to relate porosity with its generation mechanism. Third, it demonstrates that aging and porosity are correlated with: a shift from type 1 to type 2 pores, reflecting that the remodeling of existing pores is higher; an accumulation of eroded type 2 pores, reflecting an extended resorption-reversal phase; and a coalescence of these eroded type 2 pores into enlarged coalescing type 2 cavities. Collectively, this study supports the notion, that age-related increase in cortical porosity is the result of intracortical remodeling sites upon existing pores, with an extended reversal-resorption phase (eroded type 2 pores) that may likely result in a delayed or absent initiation of the subsequent bone formation. (c) 2017 The Authors. Journal of Bone and Mineral Research Published by Wiley Periodicals Inc.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available