Character's arms distortion

[kipac]

Hey guys, I found out that whenever my character moves their arms above the shoulders (ex. when they're mining, using tanning rack, chopping wood, etc), its arms distort really weird in really nasty looking. Arms become thin and squeezed, and then stretch out.

Is this distortion caused by the mods I've installed? or it was originally like this but I noticed it just now?

The mods I've installed so far are types of 'homes', 'graphics textures', 'body textures', 'areas', 'clothing', and 'armor' in categories, so I think it could be caused by either armor or body related mods.

Thanks.