Fotios Alexandros Karakostis1, Carlos Lorenzo2,3. 1. Senckenberg Center for Human Evolution and Palaeoenvironments, Eberhard Karls University at Tübingen, Rumelinstrasse 23, Tübingen, 72070, Germany. 2. Area de Prehistoria, Universitat Rovira i Virgili, Av. Catalunya 35, Tarragona, 43002, Spain. 3. Institut de Paleoecologia Humana i Evolució Social (IPHES), Campus Sescelades (Edifici W3), Tarragona, 43007, Spain.
Abstract
OBJECTIVES: This study aimed to put forth a new and precise methodology for calculating the 3D areas of hand entheses. Furthermore, it investigated some of the factors affecting hand entheses development through an assessment of their correlations and morphometric patterns. MATERIALS AND METHODS: Fifty individuals from late-medieval San Pablo were studied. The sample consisted of high-definition 3D models of 17 entheses from the first, second, and fifth hand rays. A new methodology was introduced for quantifying their areas. Precision was verified using intraobserved and interobserver tests. Both raw and relative entheseal size (ratio of entheseal size to total bone surface size) were calculated. Bivariate analyses assessed the effect of age-group on entheses as well as the correlations across entheses of muscles that act synergistically, bone length, and articular surface size. The morphometric patterns among hand entheses were explored using a multivariate analysis. RESULTS: The methodology presented no significant error. Age-group variation does not seem to affect hand entheses. In relative size, only particular pairs presented significant association and the entheses involved were not correlated with bone length or articular surface size. The multivariate analysis demonstrated high sexual dimorphism in overall entheseal size as well as two morphometric trends among hand entheses. DISCUSSION: The proposed methodology can set the basis for further morphological 3D analysis of entheses. If biomechanical stress affects hand entheses, its impact would possibly be greater on their relative size. The morphometric patterns among entheses seem to reflect the performance of prehensile grips. Am J Phys Anthropol 160:694-707, 2016.
OBJECTIVES: This study aimed to put forth a new and precise methodology for calculating the 3D areas of hand entheses. Furthermore, it investigated some of the factors affecting hand entheses development through an assessment of their correlations and morphometric patterns. MATERIALS AND METHODS: Fifty individuals from late-medieval San Pablo were studied. The sample consisted of high-definition 3D models of 17 entheses from the first, second, and fifth hand rays. A new methodology was introduced for quantifying their areas. Precision was verified using intraobserved and interobserver tests. Both raw and relative entheseal size (ratio of entheseal size to total bone surface size) were calculated. Bivariate analyses assessed the effect of age-group on entheses as well as the correlations across entheses of muscles that act synergistically, bone length, and articular surface size. The morphometric patterns among hand entheses were explored using a multivariate analysis. RESULTS: The methodology presented no significant error. Age-group variation does not seem to affect hand entheses. In relative size, only particular pairs presented significant association and the entheses involved were not correlated with bone length or articular surface size. The multivariate analysis demonstrated high sexual dimorphism in overall entheseal size as well as two morphometric trends among hand entheses. DISCUSSION: The proposed methodology can set the basis for further morphological 3D analysis of entheses. If biomechanical stress affects hand entheses, its impact would possibly be greater on their relative size. The morphometric patterns among entheses seem to reflect the performance of prehensile grips. Am J Phys Anthropol 160:694-707, 2016.