Technical note: Forearm pronation efficiency analysis in skeletal remains
Article first published online: 11 AUG 2009
Copyright © 2009 Wiley-Liss, Inc.
American Journal of Physical Anthropology
Volume 140, Issue 3, pages 589–594, November 2009
How to Cite
Galtés, I., Jordana, X., Malgosa, A. and Manyosa, J. (2009), Technical note: Forearm pronation efficiency analysis in skeletal remains. Am. J. Phys. Anthropol., 140: 589–594. doi: 10.1002/ajpa.21144
- Issue published online: 6 OCT 2009
- Article first published online: 11 AUG 2009
- Manuscript Accepted: 16 JUN 2009
- Manuscript Received: 3 DEC 2008
- CGL2005-02567/BOS. X. Jordana is a Postdoctoral Fellow of the Fundacão para a Ciência e a Tecnologia. Grant Number: SFRH/BPD/26683/2006
- pronator teres;
- humeral medial epicondyle
This work presents an original methodology for analyzing forearm-pronation efficiency from skeletal remains and its variation with regard to changes in the elbow position. The methodology is based on a biomechanical model that defines rotational efficiency as a mathematical function expressing a geometrical relationship between the origin and insertion of the pronator teres. The methodology uses humeral distal epiphysis photography, from which the geometrical parameters for the efficiency calculus can be obtained. Rotational efficiency is analyzed in a human specimen and in a living nonhuman hominoid (Symphalangus syndactylus) for a full elbow extension (180°) and an intermediate elbow position (90°). In both specimens, the results show that this rotational-efficiency parameter varies throughout the entire rotational range and show a dependency on the elbow joint position. The rotational efficiency of the siamang's pronator teres is less affected by flexion of the forearm than that of the human. The fact that forearm-pronation efficiency can be inferred, even quantified, allows us to interpret more precisely the functional and evolutionary significance of upper-limb skeletal design in extant and fossil primate taxa. Am J Phys Anthropol 2009. © 2009 Wiley-Liss, Inc.