In case you were wondering, yes, this did hurt. Macartney was airlifted to a hospital, and supposedly suffered bruising to his brain and was put in an induced coma.
He recovered quickly, however, and — we hear — jokes about the incident. So go ahead and laugh. (Although you're still a horrible person.)
[via YouTube - Careful, the full-length version is way more disturbing/less funny than our trimmed down one]