Histomorphology

Pore Extractor 2D: An ImageJ toolkit for quantifying cortical pore morphometry on histological bone images, with application to intraskeletal and regional patterning

“…Quantifying cortical porosity has broad applications in biological anthropology. Cortical porosity is a proxy of mechanical loading history, as it reflects the strain‐based patterning of bone remodeling (Stout et al, 2019 ). Cortical porosity is also a metric of bone quality and fragility.…”

“…As early as the third decade of life, bone resorption begins to outpace bone formation due to reduced physical activity, declining sex steroids, and cellular senescence (Demontiero et al, 2012 ; Infante & Rodríguez, 2018 ). Aging is consistently associated with increases in percent porosity, pore size, and pore system convergence (Stout et al, 2019 ). Consequently, cortical pore size and shape are components of some histological age‐at‐death estimation methods (Andronowski & Cole, 2021 ).…”

“…(Hughes et al, 2020 ). Consequently, the microstructural products of remodeling do not always clearly reflect intraskeletal strain patterning (Andronowski & Cole, 2021 ; Stout et al, 2019 ). Cross‐sections from skeletal elements with varying mechanical strain environments (midshaft femur, midshaft rib, and distal radius) have been reported as intraskeletally consistent in percent porosity (Hunter & Agnew, 2016 ).…”

“…Cross‐sections from skeletal elements with varying mechanical strain environments (midshaft femur, midshaft rib, and distal radius) have been reported as intraskeletally consistent in percent porosity (Hunter & Agnew, 2016 ). Within a cross‐section, however, localized variation in mechanical strain, and the resulting disparity in remodeling activity, has been shown to significantly influence microstructural patterning (Stout et al, 2019 ). Cortical porosity is elevated in lower‐strain regions, such as adjacent to the endosteum (Atkinson, 1965 ; Bousson et al, 2001 ; Jowsey, 1960 ; Martin et al, 1980 ; Thomas et al, 2005 ) and in regions under tension, as opposed to compression (Agnew et al, 2013 ; Agnew & Stout, 2012 ; Skedros, Mason, & Bloebaum, 1994 ).…”

Secondary osteon variants and remodeling in human bone

“…Osteon densities, geometric properties, and circularity have all been linked to these factors in both observation and experimentation (e.g., Britz, Thomas, Clement, & Cooper, 2009; Crescimanno & Stout, 2012; Keenan, Mears, & Skedros, 2017; Miszkiewicz, 2015; Miszkiewicz & Mahoney, 2016; Pfeiffer, 1998; Pfeiffer, Crowder, Harrington, & Brown, 2006). However, several secondary osteon variants occur within human cortical bone, including Type II and drifting osteons (Stout, Cole, & Agnew, 2019). These variants have, to date, been studied less frequently than Type I osteons and mainly using modern samples (e.g., Raguin & Drapeau, 2020; Raguin & Streeter, 2018; Robling & Stout, 1999; Watanabe, Konishi, Shimada, Ohara, & Iwamoto, 1998).…”