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View Full Version : Re: Surface markers in 3D analysis



Tochi Omenukor
12-08-1995, 06:42 PM
On Fri, 8 Dec 1995, Jesus Dapena wrote:

> > For one, it makes the use of live volunteers reasonable! Implanted
> markers are fine for cadaver studies. *In vivo* needs surface markers.
> >
>
> > Sincerely,
> >
>
> > Carolyn Small
>
> Well, there are other options too. For instance, the researcher can
> estimate the locations of the internal joints directly from the projected
> images. You sacrifice some of the accuracy in the digitization of the
> landmarks, but you can get 3D coordinates of internal landmarks without
> having to implant anything in your subjects. In fact, in some situations it
> is not possible to put even surface markers on the subjects; for instance,
> this is generally the case if you film or videotape a major sport
> competition.
>
> ---
> Jesus Dapena

despite the problems associated with surface markers [moving in to
segment endpoints, tissue movement, etc] and the unpracticability of
attachment to subjects involved in the situations mentioned [sports,
etc], i think that they would be quitea tad more comfortable than
cortical pins in a live subject [arrghhh!]. with the appropriate
connections [leds, wiring, etc], the motion of surface
markers can be recorded directly by data acquisition equiment....time
savings over other methods, yes?

tochi