Quantifying cortical bone in fragmentary archeological second metacarpals

American Journal of Physical Anthropology, vol. 174, pp. 812–821

Abstract

Abstract Objectives Skeletal variation in cortical bone thickness is an indicator of bone quality and health in archeological populations. Second metacarpal radiogrammetry, which measures cortical thickness at the shaft midpoint, is traditionally used to evaluate bone loss in bioarcheological and some clinical contexts. However fragmentary elements are regularly omitted because the midpoint cannot be determined. This methodological limitation reduces sample sizes and biases them against individuals prone to fracture, such as older individuals with low bone mass. This study introduces a new technique for measuring cortical bone in second metacarpals, the “Region of Interest” (ROI) method, which quantifies bone in archeological remains with less‐than‐ideal preservation while accounting for cortical heterogeneity. Materials and methods The ROI method was adapted from digital X‐ray radiogrammetry (DXR), a clinical method used to estimate bone mineral density, and tested using second metacarpals from Middenbeemster, Netherlands, a 19th century known age and sex skeletal collection. The ROI method quantifies cortical bone area within a 1.9 cm‐long, mid‐diaphyseal region, standardized for body size differences using total area (CAIROI). CAIROI values were compared to traditional radiogrammetric cortical indices (CI) to assess the method's ability to identify age‐related bone loss. Results CAIROI values have high intra‐ and interobserver replicability and are strongly and significantly correlated with CI values for both males (r[n = 39] = 0.906, p = 0.000) and females (r[n = 58] = 0.925, p = 0.000). Conclusion The ROI method complements traditional radiogrammetry analyses and provides a reliable way to quantify cortical bone in incomplete second metacarpals, thereby maximizing sample sizes, allowing patterns in bone acquisition and loss to be more comprehensively depicted in archeological assemblages.

Authors 6

1. Rebecca J. Gilmour corresponding

   Mount Royal University · McMaster University

   Affiliation as printed

   Department of Anthropology McMaster University Hamilton Ontario Canada

   Department of Sociology and Anthropology Mount Royal University Calgary Alberta Canada

   Department of Anthropology, McMaster University, Hamilton, Ontario, Canada

   Department of Sociology and Anthropology, Mount Royal University, Calgary, Alberta, Canada

2. Megan B. Brickley

   McMaster University

   Affiliation as printed

   Department of Anthropology McMaster University Hamilton Ontario Canada

   Department of Anthropology, McMaster University, Hamilton, Ontario, Canada

3. Menno L. P. Hoogland Aachen Faculty of Archaeology Leiden University Leiden The Netherlands Faculty of Archaeology, Leiden University

   Leiden University

   Affiliation as printed

   Faculty of Archaeology Leiden University Leiden The Netherlands

   Faculty of Archaeology, Leiden University, Leiden, The Netherlands

4. Erik Jurriaans

   Juravinski Cancer Centre · Juravinski Hospital · Hamilton Health Sciences · McMaster University

   Affiliation as printed

   Department of Radiology Juravinski Hospital and Cancer Centre, Hamilton Health Sciences Hamilton Ontario Canada

   Department of Radiology McMaster University Hamilton Ontario Canada

   Department of Radiology, Juravinski Hospital and Cancer Centre, Hamilton Health Sciences, Hamilton, Ontario, Canada

   Department of Radiology, McMaster University, Hamilton, Ontario, Canada

5. Simon A. Mays

   Historic England · University of Southampton · University of Edinburgh

   Affiliation as printed

   Department of Archaeology University of Southampton, Avenue Campus Southampton UK

   Faculty of History, Classics and Archaeology University of Edinburgh Edinburgh UK

   Research Department Historic England, Fort Cumberland Portsmouth UK

   Department of Archaeology, University of Southampton, Avenue Campus, Southampton, UK

   Faculty of History, Classics and Archaeology, University of Edinburgh, Edinburgh, UK

   Research Department, Historic England, Fort Cumberland, Portsmouth, UK

6. Tracy Prowse

   McMaster University

   Affiliation as printed

   Department of Anthropology McMaster University Hamilton Ontario Canada

   Department of Anthropology, McMaster University, Hamilton, Ontario, Canada