3+ 4/2002 - Společnost pro pojivové tkáně

tient leg forms (negative and positive). The
orthosis has two parts connected at definite
level (position) by joint and screw.The
screw operates with known force and the
orthosis pushes on leg for a sufficient time
(during night). Efficacy of orthotic treatment
is evaluated according to correction
of tibia-femoral angle measured at X-rays of
lower limbs in standing patient. There is
possibility to calculate the tibiafemoral angle
according to measurement of intermalleolar
or intercondylar distance in standing
child, anthropological estimation and comparison
with Xrays. These results are presented
in charts, too. Children's femurs and
tibias were measured with help of a computer
tomograph, and/or X – ray. Space
models of the bones have been composed.
The model is transformed to special model
of concrete patient according to patient
dimensions (bone length and diameter),
osteoporosis state (bone curvature, tibia/
femur angle).
Results: It is supposed that orthosis
and bone deformation is small with regard
to the soft parts of leg and the press on unit
length of leg and it is directly proportional
to compressive deformation and indirectly
proportional to a thick of soft leg tissue.
The prismatic beam theory with respect
Navier Bernoulli's hypotheses or the finite
element method is used for the calculation
of femur and tibia load and stress state.The
algorithm was implemented on a computer.
The stress state will be calculated at each
patient visit at orthopaedist for the actual
leg deformities and a bone remodelling will
be predicted.
Conclusion: The computer model of
bone stress state arid bone remodelling is
verified with patient's treatment course.
A part of this research is focused on determination
of algorithms for a calculation of
102
stress state at femur and tibia under force
effects of orthosis.The algorithms make possible
to calculate a stress state at bone tissue
and growth epiphyses for concrete child
patients. Mathematical relations of bone
remodelling are composed according to
stress state and time of bending pre-stressing
activity.An algorithm of bone stress state calculation,
a computer program of stress calculation
and a simulation program of system
bone stress state and bone remodelling is
a top of the presentation. Contemporary
results are very encouraging.That is why the
new developed limb orthoses with high
bending pre-stressing appear as a perspective
therapeutic method for some congenital
and acquired bone deformities especially in
preschool age.
Acknowledgments. These results have
been supported by the grant of Czech
Grant agency No. 106/00/0006.
THE CORRELATION BETWEEN THE
BONE MINERAL DENSITY AND THE
INTERVERTEBRAL DISC
DEGENERATION IN LUMBAR SPINE
H-S. Kim, K. H. Ahn, D-H.Yun,Y-G. Kim,Y-S. Jeong
Department of Rehabilitation Medicine, College
of Medicine, Kyung-hee University, #1, Hoegi-dong,
dongdaemun-gu, Seoul, 130-702, Korea
LOCOMOTOR SYSTEM vol. 9, 2002, No. 3+4
Aim of the study: To evaluate the correlation
between the bone mineral density
(BMD) and the intervertebral disc degeneration
in lumbar spine through the retrospective
study.
Materials and methods: The BMDs
and the magnetic resonance images (MRI)
of the lumbar spine were assessed, from 61
postmenopausal females (age 56.0 ± 3.7,
weight 58.9 ± 6.1 kg, height 154.9 ± 3.9
Cm), to evaluate the correlation between
the BMD and the intervertebral disc degen-