Numb fingers and a stiff neck — is it always cervical spondylosis? Follow five people — an editor with numb fingers, a sales manager with a recurring crick in the neck, a retired engineer who can no longer do up his buttons, a keen baker who feels giddy reaching for the top shelf, and a new mum who feeds with her head down — to understand three different neck problems, how doctors tell them apart, what you can do at home, how Chinese medicine sees it, and which warning signs