It sounds like a front shoulder hit? But really would help if you could give more info? where were you aiming! Which way was the deer facing? With an arrow broke off clean with no blood or hair on it my guess is a dead on shoulder hit, When the deer took off running he broke the arrow off, My brother hit a couple of deer in the past that sounds very close to what you sead happened, And he sead he hit right in the shoulder! and as soon as he started running it broke the arrow off clean without much or any blood at all. The deer he shot did not run very far!