Why Your Hands Go Numb at Night (It’s Probably Not What You Think)

Somewhere around the third or fourth time a patient tells me “I think I have carpal tunnel” before I’ve even examined them, I’ve started answering with a question instead of a nod: which fingers, exactly?

It matters more than people expect. True carpal tunnel syndrome follows a pretty specific pattern — thumb, index, middle finger, and half of the ring finger, because that’s the territory of the median nerve as it squeezes through the wrist. If someone’s pinky and the outer half of their ring finger are the ones going numb, that’s a different nerve entirely, and it’s usually not coming from the wrist at all. It’s coming from somewhere much higher up — the neck, or sometimes the space where nerves pass between the collarbone and first rib on their way down the arm.

I see a lot of this in Pleasanton, probably because there’s no shortage of people here doing desk and computer work all day — Hacienda has more office parks than I can count, and a lot of my patients spend eight-plus hours with their shoulders rounded forward and their neck craned at a screen. That posture doesn’t just strain muscles. Over time it can compress the nerve roots exiting the cervical spine, and one of the places that shows up is your hands, especially at night when you’re lying on your arm or sleeping with your neck in a position that closes down that space even further.

The reason it happens more at night isn’t mysterious once you think about it — you’re not moving around to relieve the pressure the way you do during the day, and a lot of people sleep with their arm up over their head or curled under the pillow, which is basically the worst position for both the neck and the nerve pathway through the shoulder.

So what do I actually do about it? First, I’m checking the neck, not just the wrist — looking at alignment in the cervical spine, how the first rib and collarbone are sitting, and whether there’s tension in the muscles that nerve has to pass through on its way down the arm. If the neck is where the problem is coming from, no amount of wrist splinting at night is going to fix it, though I’ll say wrist splints aren’t a bad thing to try in the meantime if you’re waking up uncomfortable.

I’m not saying carpal tunnel doesn’t exist — it absolutely does, and some of it needs more than I can offer here. But before assuming that’s what’s going on, it’s worth figuring out which fingers are actually affected and whether your neck posture during the day (and your sleep position at night) might be the actual source. I’d rather spend fifteen minutes figuring out where a problem is actually coming from than treat the symptom and have it come right back.