Middle phalanx skeletal morphology in the hand: Can it predict flexor tendon size and attachments?
Version of Record online: 13 JUN 2007
Copyright © 2007 Wiley-Liss, Inc.
American Journal of Physical Anthropology
Volume 134, Issue 2, pages 141–151, October 2007
How to Cite
Marzke, M. W., Shrewsbury, M. M. and Horner, K. E. (2007), Middle phalanx skeletal morphology in the hand: Can it predict flexor tendon size and attachments?. Am. J. Phys. Anthropol., 134: 141–151. doi: 10.1002/ajpa.20646
- Issue online: 31 AUG 2007
- Version of Record online: 13 JUN 2007
- Manuscript Accepted: 27 MAR 2007
- Manuscript Received: 27 FEB 2006
- National Institutes of Health, Division of Research Resources. Grant Number: U42 RR15090-01
- NSF. Grant Number: DGE 9987619
- primate hand;
- fossil hominins;
- flexor tendon attachments
Specific sites on the palmar diaphysis of the manual middle phalanges provide attachment for the flexor digitorum superficialis (FDS) tendon. It has been assumed in the literature that lateral palmar fossae on these bones reflect locations for these attachments and offer evidence for relative size of the flexor tendon. This assumption has led to predictions about relative FDS muscle force potential from sizes of fossae on fossil hominin middle phalanges. Inferences about locomotor capabilities of fossil hominins in turn have been drawn from the predicted force potential of the flexor muscle. The study reported here provides a critical first step in evaluating hypotheses about behavioral implications of middle phalangeal morphology in fossil hominins, by testing the hypothesis that the lateral fossae reflect the size of the FDS tendon and the location of the terminal FDS tendon attachments on the middle phalanx. The middle phalangeal region was dissected in 43 individuals from 16 primate genera, including humans. Qualitative observations were made of tendon attachment locations relative to the lateral fossae. Length measurements of the fossae were tested as predictors of FDS tendon cross-sectional area and of FDS attachment tendon lengths. Our results lead to the conclusion that the hypothesis must be rejected, and that future attention should focus on functional implications of the palmar median bar associated with the lateral fossae. Am J Phys Anthropol, 2007. © 2007 Wiley-Liss, Inc.