Tweet
Hi,
A few weeks ago, I posted a message to look for experimantal data of human joint
s. Here are the first responses I received up to now (I am still waiting for mo
re). Many thanks to all of you who offered me information, advice and other hel
ps, I sincerely appreciate them.
Huali BAO
--------------------------------------------------------------------------------
---
original posting:
Hi,all
I am a Ph.D. student in Catholique Universite de Louvain, Lovain-La-Neuve in Bel
gium. I built some mechanical models for human shoulder, elbow, hip and knee an
d developed relative methods to calculate the joint centre. Now I need some exp
erimental data to validate my models and methods. What I need precisely to calc
ulate one joint centre is 3D data of markers' position(recorded by tracking sys
tem) which are fixed on the segments the joint relates (at least three markers
per segment). The measurements errors should be, say, no more than 1-2 mm. I am
wondering if somebody out there has made similar measurement so I can use his/
her data or someone knows somewhere in Europe there is this kind of equipment w
here I can go and make some measurements.
Thanks a lot
Huali BAO
--------------------------------------------------------------------------------
--
>From stefan@mech1host.mechanik.th-darmstadt.de Thu Aug 4 14:49:56 1994
Date: Thu, 4 Aug 94 14:46:09 -1000
From: Stefan Schreiber
To: Bao@AUTO.UCL.AC.BE
Subject: Re: looking for experimantal data
Content-Length: 1234
Dear Huali Bao,
I think we did some measurements on the knee joint that you could use
for your research. We used a 3D-digitizer based on ultrasonic markers
emitting a 'click' which is measured by four microphones at a panel.
>From the different times needed by the sound waves to travel to the
mics the system calculates the coordinates of the marker in
three-space. The manufacturer claims an accuracy of 1-2mm.
I hope you are aware that in threespace there is NO SUCH THING like
an instantanious center of rotation. What you can calculate from the
data is the instantanious screw, i.e. the screw axis and the pitch.
>From your posting it is not clear what you mean by the "joint
center".
If you want, I can send you some data in plain ascii form. To a
limited extend I would take your special wishes concerning the format
into account. Since it seems we are possibly working on closely
related fields it would be nice to share some experiences and
results.
Sincerely yours
S. Schreiber
---
Dipl.-Ing. Stefan Schreiber
Institute for Mechanics I, Prof. Dr. W. Hauger
Technical University of Darmstadt
Hochschulstrasse 1
D-64289 Darmstadt
Germany
e-mail: stefan@mech1host.mechanik.th-darmstadt.de
--------------------------------------------------------------------------------
---
>From G.Ettema@mailbox.uq.oz.au Fri Aug 5 00:08:06 1994
X-Sender: angettem@dingo.cc.uq.oz.au
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Date: Fri, 05 Aug 1994 08:03:25 +1000
To: Bao@auto.ucl.ac.be
From: G.Ettema@mailbox.uq.oz.au (Gertjan Ettema)
Subject: Re: looking for experimantal data
X-Mailer:
Content-Length: 422
Dear Huali BAO,
Check with Frans C.T. van der Helm, Delft University of Technology
email: wbmrasp@DUTREX.TUDELFT.NL
He works on the shoulder and uses (or used) a 3-D measurement device. If he
doesn't use it, he will know ho does.
Regards,
Gertjan Ettema
Department of Anatomical Sciences
The University of Queensland
Queensland 4072
Australia
E-mail: G.Ettema@mailbox.uq.oz.au
Phone: (07)3652957
Fax: (07)3651299
--------------------------------------------------------------------------------
---
>From sati@grbb.polymtl.ca Fri Aug 5 15:58:01 1994
From: sati@grbb.polymtl.ca (Marwan Sati)
Subject: Re: looking for experimantal data
To: Bao@AUTO.UCL.AC.BE
Date: Fri, 5 Aug 1994 09:56:34 -0400 (EDT)
Cc: sati@grbb.polymtl.ca (Marwan Sati)
X-Mailer: ELM [version 2.4 PL23]
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 8bit
Content-Length: 3462
Dear Huali,
Concerning your request for joint kinematics to verify you mechanical
models, we may be able to help you with knee kinematics. Over the
past 2 years we have been developing a non-invasive system to measure
knee kinematics. I will provide a short description of the system.
Measuring knee kinematics is difficult due to the surrouning soft tissue.
Several authors, including ourselves, have found skin markers at the knee
to move with respect to the bone by 10 to 20 mm for active movements.
For this reason, we have put much effort into designing a mechanical system
which non-invasively clamps onto the knee to reduce skin movement. We also
obtain a 3D medical image of the subject's knee using CT scan so that we
can view the underlying 3D articular interaction. Over the past year, we
have been evaluating the movement of our system with respect to the
bone and have found it to move 3 to 4 mm RMS over 65 degrees of active
knee flexion. We are presently finalyzing the design and hope to obtain
in vivo knee kinematics and animation very soon.
Our reason for developing this system has been to incorporate real in vivo
kinematic data into a mathematical model calculating prosthetic ligament def-
ormation. We found cadaveric and mathematical kinematic models (that we
previously developed) insufficient for our purposes.
We have two students working presently to finalyze the design, accuracy eval-
uation and obtain knee kinematics and animations.
Our system seems to be less accurate than your requirements. However, I
believe for the accuracy you require, cadaveric or invasive pin measurements
are required. In vivo knee kinematics using invasive pins have been obtained
by Mario Lafortune (on biomechanics list) and Alberto Leardini ( on biomechanics
list) and Mike Murphy (M.I.T. grad, on biomech. list?). Any studies using
surface mounted markers would have errors over 5 to 7 mm RMS due to skin
movement (even if camera accuracy is of the order of 1 mm RMS).
I am interested in your study to find joint centers. Using our system, we
are presently conducting a study to find the joint center of the knee via
a "functional center of rotation" approach. I would be interested to hear how
you have gone about finding your joint centers.
Good luck with your query and give me an e-mail if there is anything
you wish to discuss,
Marwan
--
*- -*
| E-mail: sati@grbb.polymtl.ca | Mail: Biomedical Engineering |
| Marwan Sati | Ecole Polytechnique |
| Doctoral Student | P.O. Box 6079, Station `A' |
| Biomedical Engineering Dept. | Montreal, Quebec |
| Ecole Polytechnique | Canada H3C 3A7 |
| Tel.: (514) 340-4968 | Fax. (514) 340-4611 |
*- -*
*
* *
* *
* *
* *
* *
* *
* *
* *
* *
* *
* * * * **
_______________*_______ _
- _ _________________ -
--------------------------------------------------------------------------------
-----
***From h.c.schamhardt@PObox.ruu.nl Wed Aug 10 12:44:53 1994
X-Nupop-Charset: English
Date: Wed, 10 Aug 94 12:48:02 CST
From: "h.c.schamhardt"
Sender: h.c.schamhardt@nic.cc.ruu.nl
Reply-To: h.c.schamhardt@PObox.ruu.nl
To: Bao@auto.ucl.ac.be
Subject: RE: looking for experimantal data
Content-Length: 1082
Dear Huali Bao,
You wrote:
>
>Thank you very much for your response to my postiong. I am interested in you sy
stem. I would like to know more about it. Could you send me a brief description
about your system and your experiment.
>
An abstract has appeared in the Journal of Biomechanics 26: 861, 1993.
At this moment, we are one of the very few (the only?) group in the world
that has a (modified) CODA-3 system running. On the other hand, it is the
most accurate, and fastest (300 Hz) system delivering XYZ-coordinates in
meters without further calibration problems, currently available.
We are living relatively close together, so if you would like to visit us
and have a look at the system, feel free to! One practical aspect: I will
leave for Calgary, Canada, next Tuesday, and return not before the end of
August.
Best regards,
Henk
Henk C. Schamhardt
Department of Anatomy, Faculty of Veterinary Medicine
Utrecht University, P.O. Box 80.157, NL-3508 TD Utrecht
The Netherlands
phone: int+31-30-534325/534336 FAX: int+31-30-516853
Email: h.c.schamhardt@POBox.ruu.nl
***:This is actully the secind message I received from Henk C. Schamhardt.
-------------------------------------------------------------------------------
A few weeks ago, I posted a message to look for experimantal data of human joint
s. Here are the first responses I received up to now (I am still waiting for mo
re). Many thanks to all of you who offered me information, advice and other hel
ps, I sincerely appreciate them.
Huali BAO
--------------------------------------------------------------------------------
---
original posting:
Hi,all
I am a Ph.D. student in Catholique Universite de Louvain, Lovain-La-Neuve in Bel
gium. I built some mechanical models for human shoulder, elbow, hip and knee an
d developed relative methods to calculate the joint centre. Now I need some exp
erimental data to validate my models and methods. What I need precisely to calc
ulate one joint centre is 3D data of markers' position(recorded by tracking sys
tem) which are fixed on the segments the joint relates (at least three markers
per segment). The measurements errors should be, say, no more than 1-2 mm. I am
wondering if somebody out there has made similar measurement so I can use his/
her data or someone knows somewhere in Europe there is this kind of equipment w
here I can go and make some measurements.
Thanks a lot
Huali BAO
--------------------------------------------------------------------------------
--
>From stefan@mech1host.mechanik.th-darmstadt.de Thu Aug 4 14:49:56 1994
Date: Thu, 4 Aug 94 14:46:09 -1000
From: Stefan Schreiber
To: Bao@AUTO.UCL.AC.BE
Subject: Re: looking for experimantal data
Content-Length: 1234
Dear Huali Bao,
I think we did some measurements on the knee joint that you could use
for your research. We used a 3D-digitizer based on ultrasonic markers
emitting a 'click' which is measured by four microphones at a panel.
>From the different times needed by the sound waves to travel to the
mics the system calculates the coordinates of the marker in
three-space. The manufacturer claims an accuracy of 1-2mm.
I hope you are aware that in threespace there is NO SUCH THING like
an instantanious center of rotation. What you can calculate from the
data is the instantanious screw, i.e. the screw axis and the pitch.
>From your posting it is not clear what you mean by the "joint
center".
If you want, I can send you some data in plain ascii form. To a
limited extend I would take your special wishes concerning the format
into account. Since it seems we are possibly working on closely
related fields it would be nice to share some experiences and
results.
Sincerely yours
S. Schreiber
---
Dipl.-Ing. Stefan Schreiber
Institute for Mechanics I, Prof. Dr. W. Hauger
Technical University of Darmstadt
Hochschulstrasse 1
D-64289 Darmstadt
Germany
e-mail: stefan@mech1host.mechanik.th-darmstadt.de
--------------------------------------------------------------------------------
---
>From G.Ettema@mailbox.uq.oz.au Fri Aug 5 00:08:06 1994
X-Sender: angettem@dingo.cc.uq.oz.au
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Date: Fri, 05 Aug 1994 08:03:25 +1000
To: Bao@auto.ucl.ac.be
From: G.Ettema@mailbox.uq.oz.au (Gertjan Ettema)
Subject: Re: looking for experimantal data
X-Mailer:
Content-Length: 422
Dear Huali BAO,
Check with Frans C.T. van der Helm, Delft University of Technology
email: wbmrasp@DUTREX.TUDELFT.NL
He works on the shoulder and uses (or used) a 3-D measurement device. If he
doesn't use it, he will know ho does.
Regards,
Gertjan Ettema
Department of Anatomical Sciences
The University of Queensland
Queensland 4072
Australia
E-mail: G.Ettema@mailbox.uq.oz.au
Phone: (07)3652957
Fax: (07)3651299
--------------------------------------------------------------------------------
---
>From sati@grbb.polymtl.ca Fri Aug 5 15:58:01 1994
From: sati@grbb.polymtl.ca (Marwan Sati)
Subject: Re: looking for experimantal data
To: Bao@AUTO.UCL.AC.BE
Date: Fri, 5 Aug 1994 09:56:34 -0400 (EDT)
Cc: sati@grbb.polymtl.ca (Marwan Sati)
X-Mailer: ELM [version 2.4 PL23]
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 8bit
Content-Length: 3462
Dear Huali,
Concerning your request for joint kinematics to verify you mechanical
models, we may be able to help you with knee kinematics. Over the
past 2 years we have been developing a non-invasive system to measure
knee kinematics. I will provide a short description of the system.
Measuring knee kinematics is difficult due to the surrouning soft tissue.
Several authors, including ourselves, have found skin markers at the knee
to move with respect to the bone by 10 to 20 mm for active movements.
For this reason, we have put much effort into designing a mechanical system
which non-invasively clamps onto the knee to reduce skin movement. We also
obtain a 3D medical image of the subject's knee using CT scan so that we
can view the underlying 3D articular interaction. Over the past year, we
have been evaluating the movement of our system with respect to the
bone and have found it to move 3 to 4 mm RMS over 65 degrees of active
knee flexion. We are presently finalyzing the design and hope to obtain
in vivo knee kinematics and animation very soon.
Our reason for developing this system has been to incorporate real in vivo
kinematic data into a mathematical model calculating prosthetic ligament def-
ormation. We found cadaveric and mathematical kinematic models (that we
previously developed) insufficient for our purposes.
We have two students working presently to finalyze the design, accuracy eval-
uation and obtain knee kinematics and animations.
Our system seems to be less accurate than your requirements. However, I
believe for the accuracy you require, cadaveric or invasive pin measurements
are required. In vivo knee kinematics using invasive pins have been obtained
by Mario Lafortune (on biomechanics list) and Alberto Leardini ( on biomechanics
list) and Mike Murphy (M.I.T. grad, on biomech. list?). Any studies using
surface mounted markers would have errors over 5 to 7 mm RMS due to skin
movement (even if camera accuracy is of the order of 1 mm RMS).
I am interested in your study to find joint centers. Using our system, we
are presently conducting a study to find the joint center of the knee via
a "functional center of rotation" approach. I would be interested to hear how
you have gone about finding your joint centers.
Good luck with your query and give me an e-mail if there is anything
you wish to discuss,
Marwan
--
*- -*
| E-mail: sati@grbb.polymtl.ca | Mail: Biomedical Engineering |
| Marwan Sati | Ecole Polytechnique |
| Doctoral Student | P.O. Box 6079, Station `A' |
| Biomedical Engineering Dept. | Montreal, Quebec |
| Ecole Polytechnique | Canada H3C 3A7 |
| Tel.: (514) 340-4968 | Fax. (514) 340-4611 |
*- -*
*
* *
* *
* *
* *
* *
* *
* *
* *
* *
* *
* * * * **
_______________*_______ _
- _ _________________ -
--------------------------------------------------------------------------------
-----
***From h.c.schamhardt@PObox.ruu.nl Wed Aug 10 12:44:53 1994
X-Nupop-Charset: English
Date: Wed, 10 Aug 94 12:48:02 CST
From: "h.c.schamhardt"
Sender: h.c.schamhardt@nic.cc.ruu.nl
Reply-To: h.c.schamhardt@PObox.ruu.nl
To: Bao@auto.ucl.ac.be
Subject: RE: looking for experimantal data
Content-Length: 1082
Dear Huali Bao,
You wrote:
>
>Thank you very much for your response to my postiong. I am interested in you sy
stem. I would like to know more about it. Could you send me a brief description
about your system and your experiment.
>
An abstract has appeared in the Journal of Biomechanics 26: 861, 1993.
At this moment, we are one of the very few (the only?) group in the world
that has a (modified) CODA-3 system running. On the other hand, it is the
most accurate, and fastest (300 Hz) system delivering XYZ-coordinates in
meters without further calibration problems, currently available.
We are living relatively close together, so if you would like to visit us
and have a look at the system, feel free to! One practical aspect: I will
leave for Calgary, Canada, next Tuesday, and return not before the end of
August.
Best regards,
Henk
Henk C. Schamhardt
Department of Anatomy, Faculty of Veterinary Medicine
Utrecht University, P.O. Box 80.157, NL-3508 TD Utrecht
The Netherlands
phone: int+31-30-534325/534336 FAX: int+31-30-516853
Email: h.c.schamhardt@POBox.ruu.nl
***:This is actully the secind message I received from Henk C. Schamhardt.
-------------------------------------------------------------------------------