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Seetooyc
04-03-1997, 12:42 AM
Hi all:

About three weeks ago I posted a question on the inertial parameters
for children and the sampling frequency needed for dynamic analysis on
gait. Thanks to all respondents. Some of the responses have been very
helpful. The following is a list of the responses:

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My initial response to your request for information is that there
are a very limited set of questions you can ask about gait dynamics with
a
2-D approach. You will be much better off with a 3-D analysis, since
the
assumption of planar movement is routinely violated and this alters the
calculated dynamics significantly.


Larry Abraham, EdD
Kinesiology & Health Education
The University of Texas at Austin
Austin, TX 78712 USA

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One suggestion would be to contact Professor Esther Thelen at
Inidiana University. She is an expert in development and has recently
integrated the dynamic systems approach to her work.


J. Greg Anson PhD
Chair, Kinesiology Group
School of Physical Education
POB 56, Dunedin
NEW ZEALAND

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There is software developed by the Air Force that will estimate
segment and whole-body moments of inertia (for specified position)
for children in this age group based on age, weight, and height. The
software is based on stereophotometric data.


Dr. Beth A. Todd
Assistant Professor
Mechanical Engineering
Box 870276
University of Alabama
Tuscaloosa, AL 35487-0276

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De Zee, Schillings and Duysens at the University of
Nijmegen in the Netherlands have done several papers on obstructed gait
using a treadmill.

Best Regards
Christian Calame
Product Manager Biomechanics

Kistler Instrumente AG Winterthur, P.O.Box 304,
CH-8408 Winterthur, Switzerland

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Here is a paper that could be of your interest:

Growth of segment principal moments of inertia between four and twenty
years. R. K. Jensen and G. Nassas. Med. Sci. Sports Exerc. 20 (6):
594-604, 1988.

Regards
Alberto Minetti

+==================================
| Alberto E. Minetti MD |
| |
| Dept. Muscle Physiology |
| Istituto Tecnologie Biomediche |
| Avanzate - C.N.R. |
| Via Ampire 56 |
| 20131 MILANO - Italy |
| |
| LITA, Via F. Cervi 93 |
| 20090 MILANO - Italy |
+=================================+

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Regarding your questions here are some suggestions. For normative data
regarding gait in children,
you may try looking at work performed by J. Perry, or V. Inman. Both
have
published several articles, and books regarding gait in children and
adults. As for your question regarding the frequency at which to
collect
kinematic data, I am using 60Hz for my study, and I have read several
other studies that have also used this frequency for their work. The
question you have to ask yourself is, are there any "events" that are
going to occur in less than one sixtieth of a second?

Sharna Clark
Msc Candidate
University of Oregon


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I have two projects that are close to completion where we have
looked at how adults and children incoorporate the traversal of an
obstacle
(step on or step over) into their walking pattern. As the data is
finally
analyzed we can see that you receive a copy. Our children are between
ages
of 2.5 and 4.5 YO. Analysis is currently completed on the temporal
patterning of the walking 20-20 feet prior to the obstacle...we are
looking
for the dynamics involved with reference to variability and movement
shifts
(step on vs step over) conditions. We are finding it quite satisfactory
to
use 60Hz...Winter has written a lot about this. His point is that 60 Hz
is
fine for walking.

You can locate some body dimension stuff by looking in ERIC under the
American Automobile Manufacturers Association - for anthropometric data.
No
info re com or moment of intertia. Zernicke and colleagues (with Thelen
and
others) havea recently published anthrop data of the type you are
interested
in.

Joe Higgins

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