Numb fingers?

OK so this is for my husband not me lol. He is 37 and healthy and fit. For the past week or 2 his right middle and ring fingers have been randomly going numb. Mostly when he's trying to sleep and when he eats. I was wondering if it could be a pinched nerve in elbow or shoulder and what could relieve it. It's driving him nuts and making it hard for him to sleep. Any ideas??