Document Detail

Ontogenetic and regional morphologic variations in the turkey ulna diaphysis: implications for functional adaptation of cortical bone.
MedLine Citation:
PMID:  12808646     Owner:  NLM     Status:  MEDLINE    
This study examines relationships between bone morphology and mechanically mediated strain/fluid-flow patterns in an avian species. Using mid-diaphyseal transverse sections of domestic turkey ulnae (from 11 subadults and 11 adults), we quantified developmental changes in predominant collagen fiber orientation (CFO), mineral content (%ash), and microstructure in cortical octants or quadrants (i.e., %ash). Geometric parameters were examined using whole mid-diaphyseal cross-sections. The ulna undergoes habitual bending and torsion, and demonstrates nonuniform matrix fluid-flow patterns, and high circumferential strain gradients along the neutral axis (cranial-caudal) region at mid-diaphysis. The current results showed significant porosity differences: 1) greater osteocyte lacuna densities (N.Lac/Ar) (i.e., "non-vascular porosity") in the caudal and cranial cortices in both groups, 2) greater N.Lac/Ar in the pericortex vs. endocortex in mature bones, and 3) greater nonlacunar porosity (i.e., "vascular porosity") in the endocortex vs. pericortex in mature bones. Vascular and nonvascular porosities were not correlated. There were no secondary osteons in subadults. In adults, the highest secondary osteon population densities and lowest %ash occurred in the ventral-caudal, caudal, and cranial cortices, where shear strains, circumferential strain gradients, and fluid displacements are highest. Changes in thickness of the caudal cortex explained the largest proportion of the age-related increase in cranial-caudal breadth; the thickness of other cortices (dorsal, ventral, and cranial) exhibited smaller changes. Only subadult bones exhibited CFO patterns corresponding to habitual tension (ventral) and compression (dorsal). These CFO variations may be adaptations for differential mechanical requirements in "strain-mode-specific" loading. The more uniform oblique-to-transverse CFO patterns in adult bones may represent adaptations for shear strains produced by torsional loading, which is presumably more prevalent in adults. The micro- and ultrastructural heterogeneities may influence strain and fluid-flow dynamics, which are considered proximate signals in bone adaptation.
John G Skedros; Kenneth J Hunt; Paul E Hughes; Howard Winet
Related Documents :
2816516 - Biomechanical properties of the proximal femur determined in vitro by single-energy qua...
24598846 - Biomechanical measurements of stiffness and strength for five types of human and artifi...
1613586 - Optimization of follow-up measurements of bone mass.
20188416 - Bone mineral density in swedish otters (lutra lutra) in relation to pcb and dde concent...
14526636 - The value of external fixation for unstable pelvic ring injuries.
432326 - Factors influencing final range of motion in the fingers after fractures of the hand.
Publication Detail:
Type:  Comparative Study; Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology     Volume:  273     ISSN:  1552-4884     ISO Abbreviation:  -     Publication Date:  2003 Jul 
Date Detail:
Created Date:  2003-06-16     Completed Date:  2004-04-13     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  101234285     Medline TA:  Anat Rec A Discov Mol Cell Evol Biol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  609-29     Citation Subset:  IM    
Copyright Information:
Copyright 2003 Wiley-Liss, Inc.
Bone and Joint Research Laboratory, Department of Veterans Affairs Medical Center, Salt Lake City, Utah 84148, USA.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Adaptation, Physiological
Age Factors
Anatomy, Cross-Sectional
Circular Dichroism
Diaphyses / anatomy & histology,  growth & development
Fibrillar Collagens / physiology
Haversian System / anatomy & histology*,  growth & development
Muscle, Skeletal / anatomy & histology
Osteogenesis / physiology*
Regression Analysis
Turkeys / anatomy & histology*,  growth & development
Ulna / anatomy & histology*,  growth & development*
Reg. No./Substance:
0/Fibrillar Collagens

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Expression of cVg1 mRNA during chicken embryonic development.
Next Document:  Anatomical study of the pancreas in the house musk shrew (Suncus murinus), with special reference to...