Moment of Inertia of bone cross-sections

[Girish Ramaswamy]

Hello ImageJ users,

        I am trying to use ImageJ to calculate the geometric properties
specifically the moments of inertia and radii of bone cross-sections about
the X and Y axes.

        The "Moment_Calculator.class" plugin doesnt seem to work when I
run. If anyone has used ImageJ for this purpose, I would appreciate any
thoghts on this. Is there any other macro that would best fit this
purpose?

        I have 8-bit grey scale images obtained from micro-CT of the
bones.

  Thanks.

[Debra K Schneider]

Hi Girish Ramaswamy
We have obtain a wonderful macro from Robert Day from the Royal Perth Hospital to do just the measurements you want.  The only problem is that you must use an older version of ImageJ. I use version 1.35q.  If you use anything newer, I don't get the same calculated values especially in bone area. Similar but not exact values for MOI and "C"
If you are interested I can send you the zip file from Dr Day.  
Debby Schneider


----- Original Message -----
From: Girish Ramaswamy <[hidden email]>
Date: Friday, April 25, 2008 12:38 pm
Subject: Moment of Inertia of bone cross-sections
To: [hidden email]

> Hello ImageJ users,
>  
>          I am trying to use ImageJ to calculate the geometric
> properties
>  specifically the moments of inertia and radii of bone cross-sections
> about
>  the X and Y axes.
>  
>          The "Moment_Calculator.class" plugin doesnt seem to work when
> I
>  run. If anyone has used ImageJ for this purpose, I would appreciate
> any
>  thoghts on this. Is there any other macro that would best fit this
>  purpose?
>  
>          I have 8-bit grey scale images obtained from micro-CT of the
>
>  bones.
>  
>    Thanks.
>  

[Joachim Wesner]

ImageJ Interest Group <[hidden email]> schrieb am 25.04.2008 20:02:34:

> The only
> problem is that you must use an older version of ImageJ. I use
> version 1.35q.  If you use anything newer, I don't get the same
> calculated values especially in bone area. Similar but not exact
> values for MOI and "C"

Scary!! Did you look into the reason for the difference? Maybe this
is an indication of a hidden bug in newer versions of IJ that also
affects other macros!?

JW


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[Girish Ramaswamy]

     Hey Debby,

                I downloaded ImageJ recently from the website and I think it
is 1.39u. How do you say that your values are not exact? What do
you validate your MOI values against?

               Further, I am measuring tibiae which do not have a uniform
cross-section. But please do send me the zip file. I'll try running that.

          Thanks,
           Girish


On 4/25/08, Debra K Schneider <[hidden email]> wrote:

>
> Hi Girish Ramaswamy
> We have obtain a wonderful macro from Robert Day from the Royal Perth
> Hospital to do just the measurements you want.  The only problem is that you
> must use an older version of ImageJ. I use version 1.35q.  If you use
> anything newer, I don't get the same calculated values especially in bone
> area. Similar but not exact values for MOI and "C"
> If you are interested I can send you the zip file from Dr Day.
> Debby Schneider
>
>
> ----- Original Message -----
> From: Girish Ramaswamy <[hidden email]>
> Date: Friday, April 25, 2008 12:38 pm
> Subject: Moment of Inertia of bone cross-sections
> To: [hidden email]
>
>
> > Hello ImageJ users,
> >
> >          I am trying to use ImageJ to calculate the geometric
> > properties
> >  specifically the moments of inertia and radii of bone cross-sections
> > about
> >  the X and Y axes.
> >
> >          The "Moment_Calculator.class" plugin doesnt seem to work when
> > I
> >  run. If anyone has used ImageJ for this purpose, I would appreciate
> > any
> >  thoghts on this. Is there any other macro that would best fit this
> >  purpose?
> >
> >          I have 8-bit grey scale images obtained from micro-CT of the
> >
> >  bones.
> >
> >    Thanks.
> >
>

[Debra K Schneider]

Hi Joachim
I have asked several people even Dr Day, who wrote the macros, but they didn't have time to troubleshoot and I don't know how, so people suggested I just stick with the ImageJ version which worked, and that's what I have done.
Debby

----- Original Message -----
From: Joachim Wesner <[hidden email]>
Date: Friday, April 25, 2008 2:16 pm
Subject: Antwort: Re: Moment of Inertia of bone cross-sections
To: [hidden email]

> ImageJ Interest Group <[hidden email]> schrieb am 25.04.2008 20:02:34:
>  
>  > The only
>  > problem is that you must use an older version of ImageJ. I use
>  > version 1.35q.  If you use anything newer, I don't get the same
>  > calculated values especially in bone area. Similar but not exact
>  > values for MOI and "C"
>  
>  Scary!! Did you look into the reason for the difference? Maybe this
>  is an indication of a hidden bug in newer versions of IJ that also
>  affects other macros!?
>  
>  JW
>  
>  
>  ______________________________________________________________________
>  This email has been scanned by the MessageLabs Email Security System.
>  For more information please visit http://www.messagelabs.com/email 
>  ______________________________________________________________________
>