Morphometric Analysis of Variation in Human Proximal Long Bones Within and Between Populations

Abstract

Morphological variation and reactivity in human bone underpins many research questions in palaeopathology, osteoarchaeology, and anthropology. Studies on the post-crania primarily pertain to the cross-sectional geometry and epiphyseal or joint morphology and diaphyseal curvature. Very few studies address diaphyseal surface morphology. This study aims to quantify morphology of the epiphyses, diaphyseal surface morphology, and cross-sectional morphology of human proximal long bones in relation to interpopulation and intrapopulation variables including sex, age, childhood stress indicators, and pathology.
To provide some diversity in geography and temporality this research uses skeletons selected from the English medieval cemeteries of St. Guthlac’s Priory, Hereford and Fishergate House, York, the Sudanese medieval cemetery 3-J-18 from Mis Island, and the English postmedieval cemetery Coach Lane, North Shields. Cross-sectional geometry was collected via digital sectioning of 3D scans and morphological information was collected using Geometric Morphometrics. The resulting morphological and geometric sets were compared against inter and intrapopulation variables and qualitatively compared to each other to determine which limb and what part of its proximal bone is most reactive to given variables.
Morphological variation with intra and interpopulation variables was found, and its expression varied with size, age, population, bone, and morphological or geometric set. Age and morphology vary together in both epiphyseal and diaphyseal morphology, but do not appear as related in values for cross—sectional geometry. Likewise stress indicators do vary with the morphology of the diaphysis or epiphyses but the strength of their relationship often relies on the population sampled. This suggests a wealth of impact on morphology from environment, ontogenetic trajectory and development, population affinity, health, sex, life history, and age. This research highlights variation in reactivity in different anatomical areas. Crucially, this research demonstrates the morphological plasticity of the diaphyseal surface which for some variables was very reactive and is presently largely unexamined.