Josh Hader, 28, Guthrie, Oklahoma. He felt tension in his neck, stretched it the way he always did, heard the familiar crack — and at that exact moment his entire left side began to go numb. He tried to get to the refrigerator for an ice pack. He couldn’t walk in a straight line. By the time his father-in-law took him to Mercy Hospital in Oklahoma City, he already needed a wheelchair. The diagnosis: vertebral artery dissection, the vessel that connects the neck to the brain. A microscopic tear had formed a clot. Doctors had 12 minutes to administer tPA, the clot-dissolving drug, before the damage became irreversible. Dr. Vance McCollom, who treated him, explained that excessive neck manipulation puts that artery in a mechanically precarious position. Studies confirm a correlation between that habit and a higher risk of stroke, although the probability remains low. Josh survived, but was left with a walker, a patch over his right eye due to optic nerve damage, and chronic hiccups. His wife had already warned him not to do it.