Bruce and all,
Bruce referred Kevin and I to the folowing link:
>>>http://www.gcmas.org/basic_documents.html. If you read it carefully you
will see that the 2D measurements really only fall by the wayside in
relation to ankle joint rom. In fact in a relatively normal patient
population, the 2D numbers were practically identical to the 3D numbers for
sagittal plane motions at the hip and knee.The PDF file does state that in
the final conclusion that 3D measurements are ultimately better in subjects
w/ abnormal gait. Read it for yourself and make your own determination. I
did.<<<
Can I suggest you re-read it then, since their final conclusion is that:
"For gait analysis there is NO substitute for 3D motion analysis even though
the 2D method is simpler and less expensive, it produces results which are
WRONG." (capitals are those in the original text). As I stated yesterday,
you should be aware of the problems of parallax which is what this article
really addresses. Unless the hip joint (and if you use clavicle and fibula
markers) the shoulder and knee join/ leg are exaclty in the sagittal plane
the 2D measurement will fail to accuratley measure flexion / extension. To
quote conclusion 3 of the article: "Moreover, the utilization of 2D gait
analysis strategies in clinical settings where the pathology can result in
signficant "out of plane" motion is inappropriate and ill-advised". This is
referring to parallax error.
Simon
-----------------------------------------------------------------
This message was distributed by the Podiatry JISCmail list server
All opinions and assertions contained in this message are those of
the original author. The listowner(s) and the JISCmail service take
no responsibility for the content.
to leave the Podiatry email list send a message containing the text
leave podiatry
to [log in to unmask]
Please visit http://www.jiscmail.ac.uk for any further information
-----------------------------------------------------------------
|