As a rehab practitioner I am starting to get a little long in the tooth.  I barely remember graduating back in 2008.

 

One thing about getting old however is that certain cases stick with you.  One that I revisit often was a dentists wife who was thrown from a horse while at a retreat in Arizona and had small fractures in both arms.

 

The dentist came with her to the initial visit and was lamenting that he couldn’t understand why the physicians in Arizona were recommending continual icing in the management of her injury.

 

Specifically he stated that in his line of dental surgery they actually advise AGAINST ice as they feel it delays the healing response and that inflammation is a normal part of recovery and is even necessary to ensure proper tissue reformation.

 

I know in our practice at The Proactive Athlete, our views on ice have changed A LOT over our 15 years.  Initially we recommended it in the management of most injuries.  In school we were all taught the basic ‘RICE’ or ‘PRICE’ principles where the ‘I’ stands prominently in both denoting ice as essential for injury management.

 

Yet like many dogmatic practices in medical management, just because something has always been done a certain way does not mean it is the BEST way for something to be done.

 

As an aside, Dave recommended a great episode this last week from the Peter Attia Drive podcast with Dr. Marty Makary who is a Johns Hopkins surgeon that is challenging normative medical practices and uncovering many super interesting blind spots like the management of acute appendicitis or childhood antibiotic use.  Definitely worth a listen.

 

Back to ice.  You can see our evolution on ice by following our blog.  Way back in November 2012 we wrote a piece updating the PRICE (protection, rest, ice, compression and elevation) acronym to POLICE which stands for Protection, Optimal Loading, Ice, Compression and Elevation.  Not a huge advancement as ice was still in there, but it did recognize that rest is not the best for acute care management.

 

Then in August 2020 we wrote about another advancement to PRICE called PEACE and LOVE which stands for Protection, Elevation, Avoid anti-inflammatories, Compression, Education and Load, Optimism, Vascularisation and Exercise.  This was a Canadian research group that proposed this new acronym and you will notice another couple of advancements, notably that they recommend AGAINST anti-inflammatory medication for acute care management and that they introduced the mental aspect of recovery with both education and optimism where if you condition the brain for optimal recovery things tend to turn out better.

 

Again, NO ICE!

 

Maybe my Dentist client was onto something.

 

Well a very high quality study just came out in the British Journal of Sport Medicine in August that tackled the ice appropriateness debate.

 

This was a ‘critical review’ where they aggregate articles on ice and try and come up with conclusions.

 

The article itself was fairly technical and brought back horrible memories of undergraduate biochemistry and graduate level physiology.  But I will summarize the most pertinent, and interesting points, that may help guide your decision (as well as ours) on whether ice is appropriate post injury or not.  Maybe we are just recommending ice because that’s what’s always been done?

 

An interesting point on the RICE protocol was that it was first introduced in 1978 in a textbook, though physicians were using ice for injuries since the early 1900’s.

 

Just how prevalent is ice use?  The article references research showing about 80% of all emergency department consultations in the management of ankle sprains have a recommendation of ice and in a recent survey, 88% of athletes report using ice after acute sport related injuries.  To say ice use is endemic in the athletic population is an understatement and it is growing with the recent popularity of ice baths.

 

If you look at the reasons why ice has been used for so long, practitioners will cite that they think it reduces pain post injury and is beneficial in decreasing tissue metabolism limiting inflammation, swelling and haematoma formation.

 

Even if this is true…….is that actually a good thing?

 

As a primer, Dr. Mirkin who came up with the RICE protocol in 1978 mentioned above stated in a 2015 interview that “Coaches have used my ‘RICE’ guideline for decades, but now it appears that both ice and complete rest may DELAY healing, instead of helping.”

 

Huh?

 

Well what does the actual science say?

 

The most interesting thing about this review is that they only found ONE ARTICLE ON HUMAN muscle injury for ice.  And that was a small pilot study examining the feasibility of even doing a larger study on ice for calf tears.  The study did not show a difference between ice and a control group both on healing or pain perception.

 

This highlights 2 things:

 

• All research on ice is done in animals (typically rabbits or rodents) so it’s kind of tough to say for sure that it applies to humans.
• Doing a trial of ice on acute injury on humans is next to impossible. Even that little pilot study referenced above saw the authors note that to detect even a 10% difference in full recovery between the two groups, they would need to recruit 396 people with the exact same injury.  GOOD LUCK!

 

This means that there is currently no evidence for the therapeutic benefits of ice on humans.

 

This sounds like a definitive statement however, as our graduate research teacher used to always remind us, the great Carl Sagan said “Absence of evidence does not mean evidence of absence.”  Stated another way – the lack of evidence for using ice does not necessarily prove that there is no evidence for its use at all.  This holds true in this particular case as there are no human trials.

 

So what do the animal studies show (in simplified terms)?  The two biggest take home messages are:

 

• Animal studies suggest ice may impair and delay muscle regeneration following a significant muscle injury.
• Ice may offer short term pain relief in the initial hours post injury but thereafter, continued use should be done with caution to avoid potential interference with the regeneration processes.

 

To try and simplify the science of these two statements here are some pertinent points:

• In a rabbit study, applying ice post injury decreased the blood flow rate, vein diameter and limited the postinjury paw swelling for 4-6 hours. This suggests that ice may limit swelling and haematoma formation in the short term (maybe good?).
• BUT, in the long term, decreases in blood vessel volume and other blood markers were found in a rat study for 7 DAYS after just a single 20 minute ice application suggesting even this little bit of icing may delay recovery.
• Ice was also found in mice and rat studies to DELAY the recovery of muscle fibre cross-sectional area.
• Icing also seems to slow the disappearance of necrotic tissue (think dead tissue), suggesting a delay in bad tissue clearance.
• The importance of the postinjury inflammatory response has been extensively debated. It is typically considered harmful because proinflammatory cells are thought of as bad.  BUT, the newer school of thought is that despite the potential adverse effects of the acute inflammatory response, it has been shown to be 100% necessary to achieve complete muscle regeneration so why are we trying to delay this natural process?

 

Again, we have to use caution transferring this knowledge over to humans as they were done on poor rabbits, rats and mice after sustaining injuries in an experimental setting.

 

Also, the perceived pain reduction in humans using ice is real.  It can also cause use to minimize the use of pain medication which has secondary knock on effects.

 

Overall  the authors concluded that the evidence that ice benefits patient response is limited and the evidence that it benefits tissue healing is nil.

 

That’s a fairly strong statement.  They point to the fact that the early inflammatory phase following an injury is responsible for breaking down damaged tissue and promoting tissue repair.  So while blocking this early inflammatory phase by icing may provide some pain relief, animal studies suggest it may also compromise long term tissue healing and mechanical integrity.

 

The researchers that wrote this article go as far as saying that the widespread use of ice is not evidence based.  Specifically there is no evidence of a beneficial effect for continuous application of ice except for pain relief.  There is even emerging evidence of the continued use being a neg negative.  They also note that if ice were seen through the lens of being a drug, it would not be evidence based to use.

 

Again we have to remind ourselves that these conclusions are drawn from animal studies.  Also, the pain relief seen in the short term use of ice (the first few hours) is real and can be seen as a positive.

 

So the next time you consider ice after an acute soft tissue injury like an ankle sprain, perhaps the best method is to use it specifically to control pain if you need to in the short term, however the longer you use it, the greater the likelihood of it being a net negative.

 

Guess the dentist was right.