It’s common practice to throw ice on a injury in order to reduce swelling. Why does swelling need to be removed? Isn’t your body doing it for a reason?
Like almost anything the body does, it can be good or bad, depending on how much.
Yes, swelling is a sign that good things are happening - the body is sending extra blood and lymph and immune system stuff the the site. It’s also gently immobilizing the site a bit so you don’t accidentally move it around too much and risk further injury.
OTOH, too much swelling hurts. Things start to press on nerves and we don’t like that much. We also have more friendly ways to immobilize things nowadays, like restraints and splints if need be. There’s also a point at which too much swelling can cause tissue damage and slow down healing, and the body isn’t a thinking machine (well, not like that, anyway) and doesn’t always know when that point is.
If you have an injury with significant swelling, you’re not going to be able to reduce it completely with an ice pack, nor is that the goal. The goal is to reduce the swelling enough to reduce the pain.
I see. So is there no danger in reducing swelling? We’re not impeding the body’s natural healing process?
Having had unremittent swelling for a long time over my whole body, I can say it feels like every part has fallen asleep and fells like when the parts are just getting circulation back. You’re also unable to bend the swollen apendage. Inpared circulation from swelling also precipitates never damage. I still have terrible coordination, and walk like a drunk or half drunk now.
Well, I never say never, but I run with the hippies, and even the most frighteningly anti-medical establishment stuff says to ice an injury to reduce swelling. Like I said, I don’t think it’s even possible to *eliminate *swelling with ice - when I sprained my ankle, it looked like a balloon even with lots of ice - but it’s possible to *reduce *it for comfort and to help prevent nerve and tissue damage. Note: ice should always be applied in a cloth, not directly, and for no more than 20 minutes at a time, to reduce the chances of frostbite from the ice.
Remember that the body doesn’t always do what’s best for us as individuals. It does what works well enough most of the time for enough of us to breed. “Innate healing wisdom” is nice and all, but we also evolved brains to help us help ourselves.
At my recent emerg first aid course, they said that new resarch had found that icing injuries does reduce swelling and pain, but ultimately does the injury more harm that good since icing reduces the blood flow to the area and impedes healing. No cites, but they said it’s common in sports players to have internal scarring due to over-icing their injuries so they could get back into the game.
The instructor said that the coldest compress should only be lukewarm, and swelling and pain is best fought with drugs.
NB
Whoa! IANAdoctor, but I smell some very poor logic here. Maybe the scarring is not from the anti-swelling procedures, but from getting back into the game before the injury has healed?
Hrmm, that’s not what my instructor said. Cold (in the form of ice or cold water) was the first choice. Drugs can have unintended side effects.
Too much swelling is bad. Not enough swelling is bad. The challenge is in figuring out how much is right, and then attaining that goal.
The body’s defenses have a tendency to over-react. Often, the immune response to a significant infection can be so over-the-top that the patient dies of the defenses, not the infection. With injuries, the body rushes many factors to the site which can cause similar problems locally.
If one elevates the injured area higher than their heart, uses an elastic wrap firmly but not too tight, keeps ice on it no more than 20 minutes out of every hour, and takes some tylenol, one will be more likely to achieve a happy medium between too much swelling and not enough swelling.
Somewhat off topic, but the question you pose is quite reminiscent of another, related one - should we try to reduce fever or should we respect the “wisdom of the body” and leave it alone? Despite lots of arguments both ways, there is no consensus (except basically what Qad said, i.e. try to find the happy medium).
Find me a happy medium, and I’ll find you a laughing witch.
Hey, I resemble that remark! 
The way I was taught was to ice an injury immediately after for about two hours to reduce the swelling, then warmth after that to increase circulation. RICE:
Rest
Ice
Compression
Elevation
I never got to put that into practice so I can’t tell you how effective it is.
and just today i was told that for my torn lateral meniscus (no surgery, thank the gods), it was rehab, rest, ice, elevation, but no more than 20 minutes of ice at a time.
it definitely depends on what kind of injury - and where - we’re talking about, here.
My PTA husband says to alternate heat with ice after the injury has started healing. The heat increases circulation and the ice reduces swelling.
it seems to work well for us. His favorite ice bag is a bag of frozen peas.
Compartment Syndrome is what they taught us in my first responder class as being Very Bad Swelling.
Apparently, a doctor might actually cut the skin to alleviate swelling in this instance. And actual doctor may be along shortly (or not) to tell me I’m full of it.
Cheers,
G
You may want to take a peek at prolotherapy where you intentionally cause inflammation to help healing.