A major part of sports medicine is the rehabilitation of sports injuries both conservatively and post-operatively.   Although much of this requires the expertise of the sports medicine doctor, athletic trainer and/or the physical therapist, there are some basic principles which, if understood, can help everyone minimize their down time from sports related injuries.

Its been said that there are only four words that a sports medicine doctor has to know in order to practice:  put ice on it.  Though this obviously understates the vastness of the field of sports medicine, this joke does point out the untility of temperature modalities in treating musculoskeletal injuries.

Very often, people present themselves for evaluation in a sports medicine clinic for one injury or another, say for example an ankle sprain.  Their ankle may be markedly swollen but have other signs that lead the doctor to believe that it is a relatively minor sprain.  When asked what treatment they used acutely, patients will often report applying moist heat to their ankle to reduce the swelling.  Unfortunately their action had exactly the opposite effect.  

Ice is the “miracle drug” of sports medicine.  Ice serves to reduce inflammation, provide pain relief, allow for increased range of motion secondary to decreased pain and decrease swelling in an injured body part.  Ice is universally safe to use on musculoskeletal injuries and, when in doubt, should be used as opposed to heat.

Ice or cold works by several mechanisms to accomplish all of the things listed above.  One of the primary mechanisms of action of ice is vasoconstriction.  This means that when the tissues get cold, the blood vessels traversing the tissues shrink to a smaller diameter.  This decreases the blood flow to the tissue and subsequently reduces swelling and edema in the injured area. 

Ice also slows down many of the reactions that take place in the inflammatory cascade.  This is a “physical” way to accomplish more or less the same goal as we do “chemically” with the use of non-steroidal anti-inflammatory medicines.

Sports doctors often hear the people don’t like to use ice because they are afraid of getting frost bite.  This is largely a myth.  It would be difficult or impossible to get frost bite by applying ice therapeutically to an injured body part. 

People are also reluctant to use ice because it can be uncomfortable when first applied.  It should be remembered though that after a few moments of initial discomfort, the tissues in contact with the ice will become numb.

There are a couple of things to keep in mind when using ice on a sports injury.  First is that moist cold is better than dry cold.  Get the ice bag wet (assuming you’re using traditional ice in a bag) and then apply it.  Commercial ice bags work fine too and should be used according to the directions.  Believe it or not, a bag of frozen corn or peas makes a very effective and reusable ice bag.

When applying ice to an injury, a good rule of thumb is to ice 20-25 minutes several times a day.  Most injuries may be iced as frequently as 20-25 minutes per hour.  Ice should not be left on continuously.   Also, care should be taken not to ice the inside of the elbow or the outside of the knee more than about 15 minutes.

Moist heat is another extremely useful modality.  Unfortunately though, heat does not have the universally beneficial effect that ice does.

Like ice, moist heat can serve as an analgesic to reduce pain.  The difference is that heat does not typically reduce swelling and effectively vasodilates the blood vessels running through the heated tissues.  If the area is already swollen or edematous, increasing the amount of blood flowing into the tissue will only serve to make matters worse.

Heat is usually reserved for older injuries where ice can universally be used for injuries under 72 hours old.  If the injury has not been aggravated recently and has no active swelling, heat is usually beneficial..  If, on the other hand, there is active swelling or the injury has been aggravated recently (like during a sports practice) ice would be a much better choice. 

In treating chronic injuries where play is not restricted but the injury requires treatment nonetheless, the rule of thumb is heat before and ice after activity.

Of course, these are only guidelines..  Some specific injuries may be treated with regimens which are exceptions to these broad rules.  However, please keep in mind this take home message......when in doubt, use ice on musculoskeletal injuries and ask your doc.