Occasionally you chat to someone and think, “my word this person knows their stuff!” This was definitely the case when chatting to researcher and sports therapist Peter Thain. I’ve never known anyone who knows so much about ice! So I was delighted when he agreed to do a guest blog for us on the topic of ice and its use in sport. You can follow Peter on twitter via @MrThain – I suggest you do, he’s a clever man!…
Firstly, may I thank Tom Goom for inviting me to write a short piece for his blog. I frequently read the work written on the running blog as it provides a fascinating insight into the current best practises. Hopefully this piece on ice application can contribute in some way.
Before I discuss the different modalities, it is important to mention the rationale for ice application. Within the sports medicine environment, cryotherapy (just another name for ice application really) is a widely used therapeutic modality for both the treatment of acute soft tissue injures, and during rehabilitation. The immediate application of ice aims to provide a cold induced analgesic effect, thereby reducing the appreciation of pain. The magical skin temperature frequently reported in the literature to produce local analgesia is between 10 and 15°C, and this is readily achievable with most ice modalities.
Pain relief is the main reason you should be applying ice to a musculoskeletal injury, and there are numerous scientific papers that will support this. However, if we were playing family fortunes, and “we asked 100 people to name a reason to apply ice”, you can almost guarantee that ‘reduce swelling’ would earn you a star prize (probably a washing machine or cross trainer!). However, you may be surprised to learn that there is currently no research involving human subjects which supports this. So why not…?
Studies have examined the effect of ice application on metabolism (which is what the ice needs to supress) in animal studies and identified the target tissue temperature to be between 5 and 10°C. At first you may think this is achievable, however, this temperature reduction needs to be reached at depth rather than at the surface. No study to date has achieved this at 2cm below the adipose tissue. So… what does this mean for the future of ice?!
Well firstly make no mistake; ice is a fantastic modality at reducing pain. As far as reducing metabolism, for me the jury is still out. Although having said that, whilst it may not be possible to reduce the tissue at depth to 10°C, you could argue that even if the temperature declines by 1°C then that is of benefit. If you are interested in reading more on this, I would recommend the brilliant article by Dr Chris Bleakley entitled “Is it possible to achieve optimal levels of tissue cooling in cryotherapy?”
So onto the main question: “Which modality?”
The answer to this all depends on the stage of injury. I currently work in semi-professional football so forgive me for these examples, but I think the three different scenarios help to explain the rationale and are applicable to any sport.
Scenario One: Acute setting – Return to play.
The athlete has received a trauma to the ankle/ foot complex but there is no significant structural damage. Here the aim of the ice application is to provide quick pain relief before the athlete returns to activity. The best modality to use is an ice bag containing crushed ice, as it has been shown to reduce temperatures to critical levels required for analgesia within 5 minutes (Jutte, Merrick, Ingersoll & Edwards, 2001; Merrick, Jutte & Smith, 2003). You should consider the use of wet-ice application, where ice is applied through a fabric bag; this porous material provides a barrier to stop potential ice burn, whilst the residual water is in contact with the skin. As cryotherapy modalities absorb heat through conduction and evaporation, wet ice exhibits greater thermal conduction than that of its dry ice counterpart (Belitsky, Odam & Hubley-Kozey, 1987; Merrick et al., 2003).
As I am not just a researcher but a practicing sports therapist, I appreciate the need for the recommendations to be practical. I therefore use a mixture of crushed ice and water mix in a plastic bag and apply pitch-side, as wet ice applications can be messy and impractical. However, during half time, many players will receive crushed ice enveloped in a thin wet cotton cloth to their ankles for fast pain relief following contusions and heavy tackles.
Scenario Two: Acute setting – Remove from play.
The athlete has received a significant trauma to the ankle and there is significant structural damage and must cease activity. Here the ice application aims to provide pain relief, but more importantly, compression needs to be applied. In an effort to reduce the oedema from building up, the compression with shut down the available space for the fluid to accumulate. As a result, wet ice application is no use here as the compression will not be consistent as the water escapes the porous bag. Instead, the dry ice method of crushed ice should be applied in a plastic bag and attached with a compression bandage. The ice is not the most important criteria here, it is the compression.
Apply the ice for 10 minutes on, and then remove for 10 minutes. In the rest period, reapply the compression bandage. After the 10 minutes rest, reapply the ice application. Continue this cycle of 10 on, 10 off, 10 on for as long as possible. Once finished icing and before you return home, place the compression wrap back on the area.
The rationale for 10 minutes on, 10 minutes off, not only allows the skin a rest period from constant cold, but more importantly, the modalities ability to absorb heat is at its maximal for at least 10 minutes, before the modality temperature may begin to rise. Additionally, a thermal gradient is created between the skin and the intramuscular tissues, which allows cold to be reached at depth. When the ice is reapplied for a second 10 minutes, the tissue temperature at depth has not risen to pre-treatment levels and therefore can reach a lower temperature still. So, rather than the traditionally 20 minutes continuous, where the modality may start to warm after 15 minutes, here you still receive a combined total of 20 minutes ice application, but the tissueis maintained at a lower temperature for over 30 minutes.
Scenario Three: Rehabilitation
You may not be aware, but the use of cryotherapy during rehabilitation can potentially promote your recovery by using cryokinetic protocols (cryokinetics simply means cold and motion). In the instance of an ankle sprain, the athlete immerses their foot into an ice and water mix (1-4°C) until their foot becomes numb. The typical sensations you can expect to feel are burning, stinging and aching before a period of analgesia occurs after approximately 10 to 20 minutes of immersion. After this, the athlete begins to perform their rehabilitation exercises, so in the early stages simple non-weight bearing range of motion work. Continue to perform the exercises until the period of analgesia is diminished (typically 5 minutes), before immersing your foot again to achieve another period of analgesia. As you progress through the rehabilitation stages, right up to return to activity, you can still use the cryokinetic protocols. So why are we doing this…?
The ability of cryotherapy to provide an analgesic effect enables exercises to be performed earlier than would normally be possible (Bleakley, McDonough & MacAuley, 2004; Knight, Buckner, Stoneman & Rubley, 2000). The beauty of cryokinetics is that it allows the muscles to contract, and therefore they will actively pump the swelling out of the area via the lymphatic drainage system. So by applying the ice application, you can perform simple range of motion exercises early than normally would be possible, and thus reducing swelling quicker. You may have read the recent work by Bleakley, Glasgow and MacAuley (2012) who recommends calling the POLICE, where optimal loading is required. If you haven’t read this article I would recommend it, as cryokinetics allows for this optimal loading to occur sooner.
Some of you may be concerned that by performing exercises under a period of analgesia you will not be able to appreciate pain, and therefore will not know if you are causing any further damage to the tissue as a result of the exercise being too advanced for your stage of rehabilitation. This is not the case, as the ice application does not remove the pain-sensing mechanisms, but rather removes residual pain such as that caused by pressure from swelling on nerves and damaged tissue. (Hayden, 1964; Knight et al, 2000; Pincivero, Gieck & Saliba, 1993). So, if you do perform an exercise that is too advanced that will cause further damage, you WILL still perceive this pain and should therefore regress the exercise.
Ice immersion should be the chosen modality here rather than wet ice bag application as it provides a longer period of analgesia. We are not concerned with how fast it takes to cause pain relief, but rather how longit lasts. The longer the period of analgesia, the larger the window of opportunity to perform exercises.
Cryokinetics is not only effective with joint injuries but also muscle strains. I have found it to be particularly useful in the treatment of lateral ankle sprains. Pincivero et al. (1993) presented a case study and conclude that cryokinetic protocol hastened the return to activity.
So in summary:
- Athlete return to play: crushed ice in a damp cotton bag
- Athlete cease play: crushed ice in a plastic bag with compression wrap applied
- Rehabilitation: immersion to facilitate exercise
Some other considerations……
What about cold spray?
When I took up my current position, I was given a box of cold spray. I must say, it has come in very useful… I use it as pest control to kill the flies and gnats in my therapy room! I personally see no use for the spray in the field of sports medicine. Often you see therapists run on pitch side and administer the cold spray or vapocoolant. Yes, it may act as a counterirritant, but you have to question the accuracy of application. Often the spray is administered over socks and better still most of it may fly away on a windy day! You are far better applying a crushed ice and water mix.
What about instant cold packs?
Commercially available gel packs have a pre-application temperature of -14°C and therefore remain prevalent in sports clubs, with first aiders believing colder is best. However, a modalities capacity to absorb heat is far greater if required to overcome latent heat of fusion (turn from a solid to a liquid) which is not required in the already liquid gel pack. To put this to the test, when I teach undergraduate students thermal treatments, at the start of the lecture we play pass the parcel. I pass around a bag containing a crushed ice and water mix, and an instant ice pack. No sweets here I’m afraid just the gift of cold hands! This will pass 40 pairs of hands in approximately 10 minutes. When it reaches back to me we repeat it again. During the second round, the crushed ice and water mix is still as cold as it was at the beginning, yet the instant cool pack is room temperature (if not warmer after passing 80 pairs of hands). The evidence also conclusively shows that regardless of application duration, ice based modalities are superior to gel packs at reducing skin temperature (Chesterton et al., 2002; Kanlayanaphotporn & Janwantanakul, 2005; Kennet et al., 2007).
Contraindication to ice application
Athletes with a fear or intolerance to ice including Raynaud’s disease and cryoglobulinemia should not be administered cryotherapy. The risk of frost bite is very rare and can be reduced by application periods of less than 40mins (Knight, 1995). A barrier is advisable, such as crushed ice placed in a plastic or fabric bag. Cryogen gel packs should always be avoided as there are superior modalities to achieve the desired effects. Bleakley and Hopkins (2010) identified no cases of skin burns in their review of over 35 laboratory basedcryotherapy studies.
Belitsky, R. B., Odam, S. J. & Hubley-Kozey, C. (1987). Evaluation of the effectiveness of wet ice, dry ice, and cryogen packs in reducing skin temperature. Physical Therapy, 67(7), 1080-1084.
Bleakley, C. M., McDonough, S. M. & MacAuley, D. C. (2004). Cryotherapy for acute ankle sprains: a randomised controlled study of two different icing protocols. British Journal of Sports Medicine, 40, 700-705.
Bleakley, C. M. & Hopkins, J. T. (2010). Is it possible to achieve optimal levels of tissue cooling incryotherapy? Physical Therapy Reviews, 15(4), 344-350.
Bleakley, C.M., Glasgow, P. & MacAuley, D. C. (2012). PRICE needs updating, should we call the POLICE? British Journal of Sports Medicine, 46(4), 220-221.
Chesterton, L. S., Foster, N. E. & Ross, L. (2002). Skin temperature response to cryotherapy. Archives of Physical Medicine and Rehabilitation, 83(4), 543-549.
Hayden, C. (1964). Cryokinetics in an early treatment program. Journal of American Physical Therapy Association, 44(11), 990-993.
Jutte, L. S., Merrick, M. A., Ingersoll, C. D. & Edwards, J. E. (2001). The relationship between intramuscular temperature, skin temperature, and adipose thickness during cryotherapy and rewarming. Archives of Physical Medicine and Rehabilitation, 82(6), 845-850.
Kanlayanaphotporn, R. & Janwantanakul, P. (2005). Comparison of skin surface temperature during the application of various cryotherapy modalities. Archives of Physical Medicine and Rehabilitation, 86(7), 1411-1415.
Kennet, J., Hardaker, N., Hobbs, S. & Selfe, J. (2007). Cooling efficiency of 4 common cryotherapeutic agents. Journal of Athletic Training, 42(3), 343-348.
Knight, K. L., Brucker, J. B., Stoneman, P. D. & Rubley, M. D. (2000). Muscle injury management with cryotherapy. Athletic Therapy Today, 5(4), 26-30.
Knight, K. (1995). Cryotherapy in Sports Injury Management. Champaign, IL: Human Kinetics.
Merrick, M. A., Jutte, L. S. & Smith, M. E. (2003). Cold modalities with different thermodynamic properties produce different surface and intramuscular temperatures. Journal of Athletic Training, 38(1), 28-33.
Pincivero, D., Gieck, J. & Saliba, E. (1993).Rehabilitation of the lateral ankle sprain with cryokinetics and functional progressive exercise. Journal of Sports Rehabilitation, 2, 200-207.