Sensitization and Cold Weather Hands
As I’ve mentioned before, I like to use stories that relate to people’s personal experiences to help them grasp some of the concepts of pain. The following is story that I use a lot.
You’ve been outside working in the cold, maybe pulling weeds in the garden on a crisp morning, or maybe shoveling snow from the driveway. Maybe you do polar bear swimming competitions? Anyway, you get what I mean. You’ve been working outside in the cold and have developed “cold hands.” It’s the kind of cold hands where they got so cold that they kind of almost stopped feeling cold. Then something strange happens. You come inside to wash the dirt off of your hands and suddenly the water coming out of your perfectly normal water faucet feels like molten hot lava!
This is the process of sensitization in action. We have this very cool ability (pun intended), almost a superpower really, where we adapt the sensitivity of our sensations. We don’t even have to think about it. It just happens! When you’ve been out in the cold you adapt the set point to better match the steady input. In other words, you don’t notice the cold as being so cold once you “get used to it.” But, since the set point has been effectively lowered, warm now feels hot and hot feels like molten lava. The purpose is that we have some protective mechanisms in place to keep us safe and to be most concerned with and attentive to changes. So, once we’ve been in one input, like cold, for a while, we adapt to it so that we can better notice changes from that point.
Why is this important? Well, this action of sensitization happens with lots of things besides just temperature. It happens with smell, like when you enter a new room that smells a little funny and after you “get used to it” you don’t smell it so much any more. Or light, like when you come outside into the bright sun after being in a dark room it is blinding until you “get used to it.” And notice that our reactions to most of these inputs while we are sensitized is that of discomfort or distress of some sort. The hot lava water is painful and we withdraw our hands from the water. The blinding light when coming out of the dark is uncomfortable making us squint and shade our eyes. The nasty smell makes us grimace and maybe even cover our nose. The same process of sensitization happens with mechanical sensations for movement and position. We “get used to” a certain manner or degree of movement and position any large deviation from this elicits protective behavior and may be painful. And just like with the hot water example, we may change our set point in a way that “normal” movement now feels abnormal, just like the normal hot water feels like molten hot lava.
When we have sensitized cold hands and the water feels hot, what do we do? We turn the water colder until it feels like a normal amount of hot and gradually turn up the heat as our hands “get used it” and change the set point back to normal. Or we just wait in our nice warm house for a bit and let the hands warm back up more slowly but still “get used to it.”
This is what I tell my patients with painful movement: “You’re sensitized to movement right now and just like with your cold hands, you’ll need to find a way to let yourself get used to normal movement again. So, maybe we find a less straining, easier version of this movement and then gradually make it harder until it feels normal again.” This is probably the kindest and easiest way to do it. Of course you could choose to just keep your hands under the water that feels like lava (do the normal movement in the painful sensitized way) until that feels normal if you want. That might even be a faster way to do it. It just depends on if you want to feel that way for a bit and if you can tolerate it. But, I usually opt for turning the water down and gradually turning it up myself.
Here’s one last twist. Many of the common sensitized movement problems we think persist because the movement is avoided. There is no “getting used to it” process allowed. It’s taking the “rest till it gets better” approach. This may be appropriate in some cases, like an acutely inflamed strain may benefit from a small amount of inactivity. But, other than these limited circumstances, avoidance would be like having the cold hands, coming inside occasionally to put them under hot water to check if it feels normal yet, then going back outside into the cold to wait some more. Come in from the cold and find some ways to turn the water down to allow yourself to desensitize.