There’s probably a better place to get an answer but i just cant figure out how the arm/shoulder joins on to the actual body- in relation to the ribcage.
Would anyone be able to enlighten me or point me in the right direction?
It’s hard to know what you are asking, since everyone has there own way of rigging a character. If you are reffering to the way arm bones tend to grab hold of the rib cage when auto skinning, that can be fixed by unassigning/reassigning the offending vertices from/to exsisting vertice groups.
Is this an animation question or a physiology question? If I remember correctly the upper end of the humerus is relatively spherical in shape, and it’s held into a socket formed by the clavicle and scapula (top of my head, 3:30 AM, and so tired that I’m seeing mice run on walls, so I may be wrong) via tendons and ligaments.
But, since I’m pretty much out of it anyway, I would suggest doing a google search on the human body and hope the first several links are to scientific sites.