question about shoulder flexion (increasing or decreasing angle)

[ralphza]

Hi

I know you know the anatomical terminology well and use it well.

I have a little confusion regarding the term flexion.

I have read

https://en.wikipedia.org/wiki/Anatomical_terms_of_motion#Flexion_and_extension

It says

"Flexion ... decreases the angle...Extension is the opposite of flexion, describing a straightening movement that increases the angle between body parts"


I am clear on the directions of the arm in shoulder flexion and shoulder extension as they're mentioned in this pic

http://i.stack.imgur.com/bOrtx.png

 

So the most shoulder flexion would be arm raised high, based on that picture.

So all agree on direction, but if I look up degrees of shoulder flexion, for example

I see

http://i.stack.imgur.com/flMcY.gif

So 180 degrees of shoulder flexion, the most shoulder flexion, is arm raised high in front.

0 degrees is arm completely lowered

Videos discussing measuring shoulder flexion with a goniometer agree with that.. 180 degrees is arm raised high in front. 0 is arm completely lowered.

But that doesn't seem to agree with wikipedia which says flexion decreases the angle.

So i'm a bit confused over what seems contradictory.

 

 

[Function]

With specific regards to the shoulder joint(s), we're taught "anteflexion" (flexion in this case) and "retroflexion" (what you call extension). I understand that different sources still speak of flexion and extension of the joint, but I think anteflexion and retroflexion were taught to us because of this misunderstanding. In the shoulder, it is rather unclear to me the angle between which 2 parts, including the humerus, is decreasing in retroflexion (extension) and the angle between which 2 parts, including the humerus, is increasing in anteflexion (flexion).

 

Ergo, I don't like the definition Wiki gives us. We weren't taught a specific definition for flexion or extension; it was rather intuitive and logical.