Scaling relations between bone volume and bone structure as found using 3D mu CT images of the trabecular bone taken from different skeletal sites
Document type:
Proceedings Paper
Author(s):
Raeth, Christoph; Mueller, Dirk; Sidorenko, Irina; Monetti, Roberto; Eckstein, Felix; Matsuura, Maiko; Lochmueller, Eva-Maria; Zysset, Philippe K.; Bauer, Jan
Abstract:
According to Wolff's law bone remodels in response to the mechanical
stresses it experiences so as to produce a minimal-weight structure that
is adapted to its applied stresses. Here, we investigate the relations
between bone volume and structure for the trabecular bone using 3D mu CT
images taken from different skeletal sites in vitro, namely from the
distal radii (96 specimens), thoracic (73 specimens) and lumbar
vertebrae (78 specimens). We determine the local structure of the
trabecular network by calculating isotropic and anisotropic scaling
indices (alpha, alpha(z)). These measures have been proven to be able to
discriminate rod-from sheet-like structures and to quantify the
alignment of structures with respect to a preferential direction as
given by the direction of the external force. Comparing global structure
measures derived from the scaling indices (mean, standard deviation)
with the bone mass (BV/TV) we find that all correlations obey very
accurately power laws with scaling exponents of 0.14, 0.12, 0.15 (), -0.2, -017, -0.17 (sigma(alpha)), 0.09, 0.05, 0.07 () and
-0.20, -0.11,-0.13 (sigma(alpha(z))); distal radius, thoracic vertebra
and lumbar vertebra respectively. Thus, these relations turn out to be
site-independent, albeit the mechanical stresses to which the bones of
the forearm and the spine are exposed, are quite different. The similar
alignment might not be in agreement with a universal validity of Wolff's
law. On the other hand, such universal power law relations may allow to
develop additional diagnostic means to better assess healthy and
osteoporotic bone.
Keywords:
Osteoporosis; trabecular bone; Wolff's law; trabecular bone volume;
trabecular structure; scaling indices
Editor:
Molthen, RC; Weaver, JB
Book / Congress title:
MEDICAL IMAGING 2010: BIOMEDICAL APPLICATIONS IN MOLECULAR, STRUCTURAL, AND FUNCTIONAL IMAGING
Congress (additional information):
Conference on Medical Imaging 2010 - Biomedical Applications in
Molecular, Structural, and Functional Imaging, San Diego, CA, FEB 14-16,
2010
Volume:
7626
Organization:
SPIE; Medtronic, Inc; Aeroflex, Inc; Tungsten Heavy Powder, Inc
Publisher:
SPIE-INT SOC OPTICAL ENGINEERING
Publisher address:
1000 20TH ST, PO BOX 10, BELLINGHAM, WA 98227-0010 USA