I don't think they did implants back then
http://www.round-earth.com/SCM.html"What It Is and What It Does Sternocleidomastoid (SCM) is the big ropey muscle that runs from the mastoid process (the rounded bump behind your ear) to the joint between collarbones and sternum at the base of your throat. This paired muscle pulls the head forward and down, and acts as a checkrein to prevent the head from falling backward. Both of these actions are involved in rolling where you must tuck the head for safety. "