Trabecular Bone in the Bird Knee Responds with High Sensitivity to Changes in Load Orientation.
From: Department of Anthropology, Harvard University, Cambridge MA, 02138, USA. pontzer@fas.harvard.edu
The Journal of experimental biology
- Publish Date: Jan 2006
- ISSN: 0022-0949
- Volume: 209
- Issue: Pt 1
- Pages: 57-65
- Medium: Print
- Language: English
- Citation (JAMA): Pontzer H, Lieberman D E, Momin E, et al. Trabecular Bone in the Bird Knee Responds with High Sensitivity to Changes in Load Orientation.. J. Exp. Biol. Jan 2006;209:57-65
Abstract
Wolff’s law of trajectorial orientation proposes that trabecular struts align with the orientation of dominant compressive loads within a joint. Although widely considered in skeletal biology, Wolff’s law has never been experimentally tested while controlling for ontogenetic stage, activity level, and species differences, all factors that may affect trabecular bone growth. Here we report an experimental test of Wolff’s law using a within-species design in age-matched subjects experiencing physiologically normal levels of bone strain. Two age-matched groups of juvenile guinea fowl Numida meleagris ran on a treadmill set at either 0 degrees (Level group) or 20 degrees (Incline group), for 10 min per day over a 45-day treatment period. Birds running on the 20 degrees inclined treadmill used more-flexed knees than those in the Level group at midstance (the point of peak ground reaction force). This difference in joint posture enabled us to test the sensitivity of trabecular alignment to altered load orientation in the knee. Using a new radon transform-based method for measuring trabecular orientation, our analysis shows that the fine trabecular bone in the distal femur has a high degree of correspondence between changes in joint angle and trabecular orientation. The sensitivity of this response supports the prediction that trabecular bone adapts dynamically to the orientation of peak compressive forces.
Mesh Headings (Keywords): Age Factors, Animals, Biomechanics, Bone Density, Femur, Galliformes, Joints, Locomotion, Radon
Check for Full Text / PubMed Unique Identifier (PMID): 16354778
This abstract is part of PubMed, a service of the U.S. National Library of Medicine. PubMed includes more than 17 million citations from MEDLINE and other life science journals for biomedical articles. See Copyright and Disclaimers.
Linked medical terms appearing on this page are added by Healia to help readers find more information and are not part of the original PubMed document.
The data herein was last updated on July 8th, 2008 and may not reflect the most current and accurate data available from NLM.