What is the physiology of the hand around the knuckles?

Question

I've noticed that the knuckles of some people's hands pop out (the majority I believe), whereas with others they go "down" to create little hollowed-out holes where their knuckles are. What causes this?

Answer 1

Okay, you want anatomy.. It is a combination of a boney joint and ligaments and tendons. Yes everyone is built a little differently but, mostly it is cause by the tendons and ligaments being in different places

Answer 2

Read this article:

http://www.howstuffworks.com/question437.htm