Using Ice For Pain Relief in New Injuries

Some of the most common enquiries the clinic receives relate to the management of new injuries, particularly the application of ice and the length of time it should remain in place.   There are many modalities that can be used to achieve a cooling effect.  Patients have reported utilising anything from wet towels to a carefully balanced frozen chicken! The information available can be confusing and contradictory.

In 2010, the Association of Chartered Physiotherapists in Sports Medicine (ACPSM) investigated and updated the clinical evidence for using Protection, Rest, Ice, Compression and Elevation (PRICE) in acute management of soft tissue injuries.  Rex Physiotherapy uses these evidence based clinical recommendations (along with our own clinical experience and judgement) when advising patients who have sustained a new injury.  This blog will focus on the use of ice in achieving pain relief.  Just a reminder that this information is not intended to replace the care or recommendations of your healthcare provider.   ALWAYS seek a medical review if you have any doubts or worries.

How and when to apply ice:

  • Definitely apply ice after a new injury and throughout the acute phase.
  • Consider the acute phase to be approximately 0-72 hours post injury.  Seek advice if you are in any doubt.
  • Use crushed ice. (Ice cubes in a plastic bag).
  • Rex Physiotherapy advises you apply a thin wet barrier between your skin and the ice pack. (A wet tea towel or something similar).
  • To achieve pain relief the guideline recommends the minimum time for application of crushed ice is 10 minutes and that continual application of ice should not exceed 20-30 minutes.  Therefore Rex Physiotherapy advises patients to apply ice for a minimum of 10 minutes and a maximum of 20.
  • Re-application of ice should be guided by your levels of pain/discomfort and can be less than 2 hours.
  • Rex Physiotherapy advises that you do not apply ice at a time you are likely to fall asleep.  Do not position the ice in such a way that you can compress it between your body and another surface.  Although extremely rare, the weight of the tissues against the ice may allow excessive cooling causing an ice burn.

So why does it have to be crushed ice?  Why can’t I use my peas?

Ok.  Here comes the science bit.  Optimal cooling for pain relief is achieved when your skin temperature drops to 13 °C or below.  The current evidence confirms that these clinically significant temperature reductions are most quickly achieved using crushed ice as a cooling modality for durations of 5-15 minutes.

Additional studies have shown that other methods of cooling (frozen peas, gel packs, cryo-cuffs) produced skin temperature reductions that were outside the defined critical range of less than 13 °C after 5-20 minutes of application. (Basically, they don’t cool the skin enough to get effective pain relief).  Additionally, each cooling modality has a different cooling potential.  A gel pack for example has a pre-application temperature as low as -14°C,  but it is extremely difficult to estimate the surface temperature of a commercial gel pack during use.  This could expose the patient to ineffective cooling or extreme temperature gradients.

Solid crushed ice at 0°C has much more potential to extract heat energy.  As it melts, it stays close to 0 °C throughout the treatment; delivering consistent effective cooling.  This doesn’t mean you can’t use your peas; of course you can.  Just be aware that crushed ice has a better capacity for achieving pain relieving effects more quickly.

Reference:

Bleakley C M, Glasgow P D, Phillips N, Hanna L, Callachan M J, Davison G W,  Hopkins Ty J, E Delahunt E. (2010):  Management of acute soft tissue injury using Protection,Rest, Ice, Compression and Elevation: Recommendations from the Association of Chartered Physiotherapists in Sports and Exercise medicine (ACPSEM)