Does inflammation help to heal injured tissue

Factual Questions
1

Reading up on it, one of the treatment protocols for healing a damaged nerve, ligament or tendon is to reduce inflammation around the injury. There are a variety of ways to do this (NSAIDs, cortisone, etc).

So why is that a good thing? Isn’t the body enacting an inflammatory response for a reason? It was my understanding that inflammation helps move raw materials to heal the wound to the site as well as help move waste products out. But inflammation is almost always treated as a bad thing with an injury.

What are the negative repercussions of trying to reduce inflammation at an injury site when the body is trying to create it?

It is my understanding that inflammation helps heal muscles. Does it help nerves, tendons or ligaments as well or is it just a threat to be controlled? If it is a threat (which the medical community seems to treat it as), why did we evolve to do it?

2

As I understand it, the biological function (such as it is) of inflammation is to fight infection, not to promote healing. It may also arise as by-product of increased metabolic activity in the area due to the healing process. In neither case it is promoting healing as such, and if there is otherwise little danger of infection, reduction of inflammation (other things being equal) will probably promote healing rather than hinder it.

3

The way I understand it is that, when it comes to an injury, inflammation has, at least in part, something to do with blood moving to that area to promote healing. Again, it’s my understanding that it’s why we moved away from ‘ice it’ to ‘ice for an hour, no ice for an hour’ or some variation of that. Ice on to reduce inflammation and pain, but then taking away the ice to allow blood back in so the injury can heal.

FTR, I do understand that you’re also taking the ice away to reduce the chance of frostbite and vasoconstriction which will really not let enough blood in. And, now that I say that, it’s off to wiki which I’ll bet answers this questions pretty well.

4

Here’s some light reading for you. In short, yes, it does help, but in the few minutes I poked around, I’m not totally sure on why. I think the TLDR reason is that it moves blood to the injury site. The problem is that we don’t like the way things feel when their inflammed so we do what we can to bring the swelling down.

Inflammation - Wikipedia (Scroll around in this one as well)
Healing - Wikipedia
Eicosanoid - Wikipedia
Eicosanoid - Wikipedia

5

A fever is unpleasant and we take drugs to get rid of that but a fever has a healing motive when you have an infection.

With inflammation I assume it helps the muscles. But muscles heal faster than tendons, ligaments or nerves. Tendons and ligaments can take weeks or months to heal, nerves can take several months. Muscles usually heal in a few days to a week in my experience.

So I don’t know if increasing blood flow to the tissue would matter if a nerve or tendon is injured.

6

As a medical friend once told me, fever & inflammation are ways the body tries to fight infection – but now we can fight infections better with antibiotics. And the side effects of antibiotics are less unpleasant than fever or inflammation. So doctors prescribe antibiotics for the infection, and other medications to reduce the effects of fever and inflammation.

7

In some cases, it looks like we’re wrong about that. It’s a sacred cow that’s putting up a hell of a fight, but very slowly, it looks as though RICE, the holy sacred treatment for injury (Rest, Ice, Compression, Elevation), and the ice part in particular, is being shown to be absolutely wrong, for precisely the reason that it *reduces *inflammation.

Even the guy who invented RICE now admits that he had no evidence for doing it, and it’s probably not the best treatment, and that inflammation is in fact a good thing that promotes healing.

http://stoneathleticmedicine.com/2014/04/rice-the-end-of-an-ice-age/

Now, there’s a level of inflammation which can actually be dangerous and threaten little things like breathing and blood flow to the extremities. Obviously, in those cases, reducing inflammation is vital to save the life or limb - but yeah, we may have to sacrifice some expediency in healing in order to preserve life and limb.

It’s not “ice for an hour, no ice for an hour.” It’s not even “ice 20 on, 20 off,” which is what I learned just a few years ago in nursing school. Now it’s looking more like, “ice for 5-10 minutes to reduce the pain, then start your physical therapy.”

8

Rest, Ice, Coffee, Explosion

#TakeItSleazy

9

I’m gonna have to disagree with you on that.

Consider this experiment:

After washing the area with iodine or alcohol, make small cut in your skin with a sterile razor. Is it not going to be a bit red and tender the next day? And, if you feel or look closely, is the area of the cut not a bit raised compared to the rest of the skin. In other words, it’s swollen.

That thought experiment (you can make it real if you want) encapsulates most of the features of inflammation - pain, redness, swelling, and heat. And, the inflammation you could cause in that way is not to fight infection (although I will grant that in this sort of example, it may be helping to prevent infection). The inflammation is to promote healing, independent of infection.

Except for the pain, the other features of inflammation (swelling, redness, and heat) are due to increased blood flow into the affected area. Intuitively, that’s a good thing because whenever and wherever a part of the body is injured, supplies for repair, and the effectors of repair (specialized cells), must be brought to the area.

But, any attempt to talk about inflammation is dicey because there are different types of inflammation, or at least there’s inflammation at different scales of both time and location.

Whereas acute inflammation (as above) is necessary for repair and healing, chronic inflammation tends to be more associated with disease. And, whereas the obvious signs of inflammation we see at the site of a cut on the skin, or around a broken ankle, are just that - obvious, - a LOT of disease-associated inflammation is invisible to the naked eye. All those" itis’s" you hear about? Well ‘itis’ means inflammation and many of them don’t really have much in the way of (macroscopic) swelling, redness, or heat and often not pain either. But inflammation is definitely what they are. Their name emphasizes it. Nephritis (kidney inflammation), myocarditis (heart muscle), pneumonitis (lungs), hepatitis (liver), etc., etc.

BTW, another example of inflammation having nothing to do with infection occurs after heart attack, where the heart muscle gets damaged. If you look at the site of damage through a microscope, you see typical signs of inflammation. Same with damage to any body tissue, e.g. after a stroke. Nil to do with infection.

This is a HUGE area and rather than me going on and on about what I think is relevant, it’s probably better if people just ask. Then I, but hopefully also people who actually know something about inflammation can answer.

10

Its easy to get a bit ahead of yourself on such a topic.

What seems to be happening with heart attack is that the body knows how to try to recover from it.

So there is a lump of muscle thats turning necrotic due to lack of oxygen, and it may well then get infected and turn a minor heart attack into a fatal heart attack. So thats why there are heart attack enzymes ? Seems the body knows how to reduce the chance of infection by erasing the dead muscle just as quick as possible… before it gets infected.

And as well the inflammation will prevent infection …block the pathogen entering, push it and its poisons out, and stop the blood flow from the capillaries.

11

Wow, thanks for that link. I didn’t know the inventor of the RICE protocol says it is a bad idea. Every medical bit of advice I run across treats inflammation as a useless, destructive aspect of internal tissue healing and list ways to combat it (ice, NSAIDs, cortisone, etc).

I was under the impression ice was only good at the first stages of injury (the first few hours), after that heat was better. I’ve heard some people say alternating ice and heat works to create a pump like action to move blood and lymph in and out of hte injury site.

12

My orthopedist says extended periods of inflammation can lead to bone and cartilage loss. I assume extended inflammation is generally bad and not a sign of healing.

13

Infection implies… well, infection, with a bacterial, fungal, viral, or prion organism. Self-induced or autoinflammatory diseases are not infections. Inflammation follows infection because tissues that are damaged (as well as pathogenic organisms, see above) release molecules that attract cells and other molecules.

Inflammation does not prevent infection. Inflammation is a response TO infection (and anything that damages tissue). The most common cardiac disease in humans, atherosclerosis, is not caused by an infection, but by fat deposits, for example. Necrotic tissue DOES attract inflammatory cells, of which there are various different kinds. They can do stuff from killing other cells, neutralize viruses, to clean up and repair tissue.

Part of the problem with wound repair, though, is that the tissue is too damaged and the repair mechanisms the body has are not enough to bring the organ back to functional levels.

And I should stop before confusing someone else.

KG, the KG who is a pathologist and deals and teaches this material day in and out.

14

I’m pretty much just a layman former-recreational-athlete (and I didn’t even stay at a Holiday Inn last night), but have recovered from minor injuries and fairly major joint surgery, and my thoughts are:

“Inflammation” is a complex phenomenon, and my guess is that parts of it are useful for preventing and fighting infection (particularly in environments less sterile than post-industrial society), and parts of it are useful for healing. [I’m specifically saying 'useful to avoid the issue of what was created through adaptive selection and what wasn’t]

That said, there’s no reason to think the body would every time get the optimal level of inflammation, and, similar to high fever, there could be, and almost certainly are, situations where the body’s reaction could be worse than the underlying problem.

And, in an injury/wound, there’s physical damage that can cause swelling (e.g. broken blood vessels causing blood to accumulate) that’s separate from any ‘inflammation’ reaction, and in many cases it is probably helpful to prevent some of this swelling

15

In the above link there is another link to a page on that blog titled “Why Ice and Anti-inflammatory Medication is NOT the Answer.”

On that page the claim is made:

That makes it seem that the Editor in Chief of The Physician and Sports Medicine Journal agrees that ice should not be used following an injury. But he didn’t actually say that. He just says that there is a reason for the body’s natural inflammatory response and it’s not a bad thing. On Dr. Nick DiNubile’s website he states the following:

I don’t find that the guy that came up with the acronym RICE very compelling evidence that ice shouldn’t be used for injuries. Ice has been used much longer than that acronym has existed.

Study thaws mystery of ice’s healing properties

Prolonged Superficial Local Cryotherapy Attenuates Microcirculatory Impairment, Regional Inflammation, and Muscle Necrosis After Closed Soft Tissue Injury in Rats

16

I’m going to try and take a stab ( :slight_smile: ) at it.

OK, yes, an inflammatory response is supposed to bring materials that would help treat/cure/end whatever it is that caused the insult. They can also, eventually, bring other cells that would induce healing and clean up.

There are various points and reasons why they want to regulate the level of inflammation, and I’ll try to take different parts and explain below.

  1. Sometimes the inflammation is caused because the body is fighting against itself. This is the case with some joint diseases, for example. The cells that are supposed to protect us decide that some of our own cells are defective or foreign and attack those. In these group of conditions, then yes, modulating the inflammatory response is a way to prevent the immune system from destroying ourselves. Otherwise the immune system will continue attacking, creating more crippling damage.

  2. Sometimes the levels of inflammation are excessive. Some organisms can incite the immune system to go overboard in their “destruction mode”. This means a lot of collateral damage, as the tissue surrounding the affected area is crippled and damage. In some cases and tissues, the tissues can handle some collateral damage ok. But others can’t. Hence modulate inflammation so that the immune system does not go overboard and damage the tissues that don’t need to be damaged.

2a. Related to the above, tissues that have limited/suboptimal replication potential, such as tendons and nervous system, are sensitive to collateral damage. Makes more sense to protect those tissues than others (say skin).

  1. There is a difference between non healing, functional but suboptimal healing, and optimal healing. Excess inflammation can bring about clean up and wound healing mediators that can create suboptimal healing in some tissues. Wounds that are too big or that are affected by excessive inflammation tend to heal by fibrosis (filling of connective tissue, scar tissue), while other types of insults can heal back leaving little scarring.

We can survive with suboptimal but functional healing in some organs, but others are too delicate, and for optimal healing, inflammation has to be kept in check, so that there is the minimum amount of scarring.

Visualize: I have easily a 6-inch long scar going down the skin of my upper arm. It causes no problem to me there. A similar 6 inch long strip of connective tissue down my muscle would cause my arm muscles to not be as effective as it was before, but I could likely still be able to use that muscle. Suboptimal, but still functional. A similar scar going down my major nerves? Meeeh, great problems, at least short term, with using that arm. Would I have been able to survive and reproduce? Yea, likely. Able to use that arm properly? More problematic.

Same six inch scar in my heart or brain? Goodbye, I may be dead.

17

I’d say that’s a pretty good ‘rule of thumb’. By and large, chronic inflammation tends to lead to undesirable effects. On the other hand, in a number of situations, the presence of chronic inflammation is probably better than having none at all.

For example, if the inflammation is in response to infection, then its absence might lead to the underlying infection getting out of control. Infection with TB is a case in point, i.e. we do, in fact, see TB becoming ‘re-activated’ when people who have old, totally controlled, contained, and asymptomatic TB infection, receive drugs that turn off their immune/inflammatory system.