Hip contact forces of Gait3D

Hi everybody,

my name is Tim and I’m currently working at the university of ulm,
germany.

The reason for using the AnyBody software is to get the internal
loads of the muskuskeletal system during daily activities.

Therefore I’ve used the Gait3D model from the Repository 6 and
compared the resultant hip contact forces with the in vivo data given
by Bergmann et al. on the HIP98 CD.
The Gait3D model showed much higher contact forces as already
mentioned in the webcast of Catherine Manders from 29. January 2008.
In the webcast of J. Rasmussen (Gait Modeling, 31. August, 2006)
there was mentioned that the change to another set of GRF improves
the hip contact forces alot.

Due to this, I’ve some qeustions:

  • Are the higher hip contact forces with the dataset of Vaughan
    unphysiological high?

  • Which GRF values were used for the simulations showed in the
    webcast “Gait Modeling”, that led to improved hip contact forces?

  • Are there efforts taken to simulate the patient specific gait
    patterns from the Hip98 CD to get the opportunity to directly compare
    the hip contact forces with the in vivo measurements for validation
    purposes?

Best regards,
Tim

Hi Tim

Looking at the hip reactions reported in the literature there is
considerable variation

In the paper by Bergmann et al [1], the reported forces peaks reach values
up to 324% BW for 4 km/h gait , and 467% BW for one subject walking at 3
km/h

Brand et al [2] has values reaching also about 325% BW, I am not sure for
which speed.

[1] G. Bergmann, F. Graichen, and A. Rohlmann, “Hip joint loading during
walking and running, measured in two patients.” J Biomech, vol. 26, no. 8,
pp. 969–990, Aug 1993.

[2] Brand, et al. (1994) J. Arthro. 9(1)45-51

So I think the results of the model will reflect this, there will be a wide
variation depending on the particular load case applied.

Please also have a look at these videos:

Walking speed 3 km/h

http://www.orthoload.com/files/video/result/ebl4628b_screen.wmv

Walking speed 4 km/h

http://www.orthoload.com/files/video/result/ebl275c_screen.wmv

Here you can see forces reaching up to 337%BW

I am not sure which data has been used for the graph in the webcast, sorry.

I do not think there is a current effort to replicate some of the Hip98
experiments, but it would be really nice to do this.

Please be aware that the new repository7 contains a new gait model
GaitUniMiami which motion is created using an external application
GaitApplication2, please see posting #2159 by Michael Skipper Andersen. In
the GaitUniMiami model there is a 15 step procedure on how to create a model
based on a C3D file, I am mot sure if there is C3D files available for the
Hip98 data, but it would still be possible to do the model using the
GaitApplication2, as long as you can get trajectory files for each marker.

Please write again if you have further questions

Best regards

Søren, AnyBody Support


From: anyscript@yahoogroups.com [mailto:anyscript@yahoogroups.com] On Behalf
Of timwehner
Sent: 16 June 2008 17:59
To: anyscript@yahoogroups.com
Subject: [AnyScript] Hip contact forces of Gait3D

Hi everybody,

my name is Tim and I’m currently working at the university of ulm,
germany.

The reason for using the AnyBody software is to get the internal
loads of the muskuskeletal system during daily activities.

Therefore I’ve used the Gait3D model from the Repository 6 and
compared the resultant hip contact forces with the in vivo data given
by Bergmann et al. on the HIP98 CD.
The Gait3D model showed much higher contact forces as already
mentioned in the webcast of Catherine Manders from 29. January 2008.
In the webcast of J. Rasmussen (Gait Modeling, 31. August, 2006)
there was mentioned that the change to another set of GRF improves
the hip contact forces alot.

Due to this, I’ve some qeustions:

  • Are the higher hip contact forces with the dataset of Vaughan
    unphysiological high?

  • Which GRF values were used for the simulations showed in the
    webcast “Gait Modeling”, that led to improved hip contact forces?

  • Are there efforts taken to simulate the patient specific gait
    patterns from the Hip98 CD to get the opportunity to directly compare
    the hip contact forces with the in vivo measurements for validation
    purposes?

Best regards,
Tim

[Non-text portions of this message have been removed]

Hi Søren,

thanks a lot for your reply.

I agree with you that the variations of the reported hip contact
forces allow the assumption that the calculations with the model
driven by the data of Vaughan et al. are not unphysiological.

Otherwise I still think that it would be very interesting to simulate
the measured patients movement of Bergmann et al. because the HIP98
data provides enough data for discussing the influence of the input
data for the same patient…

I’ve have a further question, at this time a very technical one:

Is it possible to implement an IF … THEN … command in the AnyBody
script?

Best regards
Tim

— In anyscript@yahoogroups.com, “AnyBody Support” <support@…>
wrote:
>
> Hi Tim
>
>
>
> Looking at the hip reactions reported in the literature there is
> considerable variation
>
>
>
> In the paper by Bergmann et al [1], the reported forces peaks reach
values
> up to 324% BW for 4 km/h gait , and 467% BW for one subject walking
at 3
> km/h
>
>
>
> Brand et al [2] has values reaching also about 325% BW, I am not
sure for
> which speed.
>
>
>
> [1] G. Bergmann, F. Graichen, and A. Rohlmann, “Hip joint loading
during
> walking and running, measured in two patients.” J Biomech, vol. 26,
no. 8,
> pp. 969–990, Aug 1993.
>
> [2] Brand, et al. (1994) J. Arthro. 9(1)45-51
>
>
>
> So I think the results of the model will reflect this, there will
be a wide
> variation depending on the particular load case applied.
>
>
>
> Please also have a look at these videos:
>
>
>
> Walking speed 3 km/h
>
> http://www.orthoload.com/files/video/result/ebl4628b_screen.wmv
>
>
>
>
>
> Walking speed 4 km/h
>
> http://www.orthoload.com/files/video/result/ebl275c_screen.wmv
>
>
>
> Here you can see forces reaching up to 337%BW
>
>
>
> I am not sure which data has been used for the graph in the
webcast, sorry.
>
>
>
> I do not think there is a current effort to replicate some of the
Hip98
> experiments, but it would be really nice to do this.
>
> Please be aware that the new repository7 contains a new gait model
> GaitUniMiami which motion is created using an external application
> GaitApplication2, please see posting #2159 by Michael Skipper
Andersen. In
> the GaitUniMiami model there is a 15 step procedure on how to
create a model
> based on a C3D file, I am mot sure if there is C3D files available
for the
> Hip98 data, but it would still be possible to do the model using the
> GaitApplication2, as long as you can get trajectory files for each
marker.
>
>
>
> Please write again if you have further questions
>
>
>
> Best regards
>
> Søren, AnyBody Support
>
>
>
>
>
>
>
>
>
>
>
> _____
>
> From: anyscript@yahoogroups.com [mailto:anyscript@yahoogroups.com]
On Behalf
> Of timwehner
> Sent: 16 June 2008 17:59
> To: anyscript@yahoogroups.com
> Subject: [AnyScript] Hip contact forces of Gait3D
>
>
>
> Hi everybody,
>
> my name is Tim and I’m currently working at the university of ulm,
> germany.
>
> The reason for using the AnyBody software is to get the internal
> loads of the muskuskeletal system during daily activities.
>
> Therefore I’ve used the Gait3D model from the Repository 6 and
> compared the resultant hip contact forces with the in vivo data
given
> by Bergmann et al. on the HIP98 CD.
> The Gait3D model showed much higher contact forces as already
> mentioned in the webcast of Catherine Manders from 29. January 2008.
> In the webcast of J. Rasmussen (Gait Modeling, 31. August, 2006)
> there was mentioned that the change to another set of GRF improves
> the hip contact forces alot.
>
> Due to this, I’ve some qeustions:
> - Are the higher hip contact forces with the dataset of Vaughan
> unphysiological high?
>
> - Which GRF values were used for the simulations showed in the
> webcast “Gait Modeling”, that led to improved hip contact forces?
>
> - Are there efforts taken to simulate the patient specific gait
> patterns from the Hip98 CD to get the opportunity to directly
compare
> the hip contact forces with the in vivo measurements for validation
> purposes?
>
> Best regards,
> Tim
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

Hi Tim

It is possible to use if functions to some extend in the current version, it
has function like

Iffun : if function

Eqfun: equality function

Ltfun : Less than function

Gtfun: greater than function

And so on…

These function can be used in expressions for various purposes, for example
to contact detection, so if a distance is close enough some muscles used for
creating contact will obtain a high strength which is otherwise zero, but
it is not possible to create drivers using these equations.

In the forthcoming version 3.1 some expansion will be included that will
make it possible to create “ifdef” like statements in the script; this can
be used for making certain parts of the script active instead of others. If
a certain part of the script is active or not, will be determined at load
time.

I fully agree with you that it would be very interesting to create model
based on the Hip98 data since this seem to contain a full dataset.

I hope this answered the question otherwise please write again.

Best regards

Søren, AnyBody Support


From: anyscript@yahoogroups.com [mailto:anyscript@yahoogroups.com] On Behalf
Of timwehner
Sent: 18 June 2008 18:30
To: anyscript@yahoogroups.com
Subject: [AnyScript] Re: Hip contact forces of Gait3D

Hi Søren,

thanks a lot for your reply.

I agree with you that the variations of the reported hip contact
forces allow the assumption that the calculations with the model
driven by the data of Vaughan et al. are not unphysiological.

Otherwise I still think that it would be very interesting to simulate
the measured patients movement of Bergmann et al. because the HIP98
data provides enough data for discussing the influence of the input
data for the same patient…

I’ve have a further question, at this time a very technical one:

Is it possible to implement an IF … THEN … command in the AnyBody
script?

Best regards
Tim

— In anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com,
“AnyBody Support” <support@…>
wrote:
>
> Hi Tim
>
>
>
> Looking at the hip reactions reported in the literature there is
> considerable variation
>
>
>
> In the paper by Bergmann et al [1], the reported forces peaks reach
values
> up to 324% BW for 4 km/h gait , and 467% BW for one subject walking
at 3
> km/h
>
>
>
> Brand et al [2] has values reaching also about 325% BW, I am not
sure for
> which speed.
>
>
>
> [1] G. Bergmann, F. Graichen, and A. Rohlmann, “Hip joint loading
during
> walking and running, measured in two patients.” J Biomech, vol. 26,
no. 8,
> pp. 969–990, Aug 1993.
>
> [2] Brand, et al. (1994) J. Arthro. 9(1)45-51
>
>
>
> So I think the results of the model will reflect this, there will
be a wide
> variation depending on the particular load case applied.
>
>
>
> Please also have a look at these videos:
>
>
>
> Walking speed 3 km/h
>
> http://www.ortholoa
<http://www.orthoload.com/files/video/result/ebl4628b_screen.wmv>
d.com/files/video/result/ebl4628b_screen.wmv
>
>
>
>
>
> Walking speed 4 km/h
>
> http://www.ortholoa
<http://www.orthoload.com/files/video/result/ebl275c_screen.wmv>
d.com/files/video/result/ebl275c_screen.wmv
>
>
>
> Here you can see forces reaching up to 337%BW
>
>
>
> I am not sure which data has been used for the graph in the
webcast, sorry.
>
>
>
> I do not think there is a current effort to replicate some of the
Hip98
> experiments, but it would be really nice to do this.
>
> Please be aware that the new repository7 contains a new gait model
> GaitUniMiami which motion is created using an external application
> GaitApplication2, please see posting #2159 by Michael Skipper
Andersen. In
> the GaitUniMiami model there is a 15 step procedure on how to
create a model
> based on a C3D file, I am mot sure if there is C3D files available
for the
> Hip98 data, but it would still be possible to do the model using the
> GaitApplication2, as long as you can get trajectory files for each
marker.
>
>
>
> Please write again if you have further questions
>
>
>
> Best regards
>
> Søren, AnyBody Support
>
>
>
>
>
>
>
>
>
>
>
> _____
>
> From: anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com
[mailto:anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com]
On Behalf
> Of timwehner
> Sent: 16 June 2008 17:59
> To: anyscript@yahoogrou <mailto:anyscript%40yahoogroups.com> ps.com
> Subject: [AnyScript] Hip contact forces of Gait3D
>
>
>
> Hi everybody,
>
> my name is Tim and I’m currently working at the university of ulm,
> germany.
>
> The reason for using the AnyBody software is to get the internal
> loads of the muskuskeletal system during daily activities.
>
> Therefore I’ve used the Gait3D model from the Repository 6 and
> compared the resultant hip contact forces with the in vivo data
given
> by Bergmann et al. on the HIP98 CD.
> The Gait3D model showed much higher contact forces as already
> mentioned in the webcast of Catherine Manders from 29. January 2008.
> In the webcast of J. Rasmussen (Gait Modeling, 31. August, 2006)
> there was mentioned that the change to another set of GRF improves
> the hip contact forces alot.
>
> Due to this, I’ve some qeustions:
> - Are the higher hip contact forces with the dataset of Vaughan
> unphysiological high?
>
> - Which GRF values were used for the simulations showed in the
> webcast “Gait Modeling”, that led to improved hip contact forces?
>
> - Are there efforts taken to simulate the patient specific gait
> patterns from the Hip98 CD to get the opportunity to directly
compare
> the hip contact forces with the in vivo measurements for validation
> purposes?
>
> Best regards,
> Tim
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

[Non-text portions of this message have been removed]