Jump to comment:

• Cryotherapy research: methods, quality and dosage
  Chris M Bleakley
  Published on: 29 April 2016
• Ice / Cryotherapy and STI managment
  Stephen H Boyce
  Published on: 29 April 2016

• Published on: 29 April 2016

  Cryotherapy research: methods, quality and dosage

  • Chris M Bleakley, Researcher

  The author is commended on developing the evidence base for the common clinical practice of ice application. However, there are a number of issues with the methodological procedures and final conclusions that I feel need to be discussed. In particular, I do not feel that this review provides a fully accurate and up to date summation of the current evidence base for using cryotherapy in acute injury management.

  ...

  Show More

  The author is commended on developing the evidence base for the common clinical practice of ice application. However, there are a number of issues with the methodological procedures and final conclusions that I feel need to be discussed. In particular, I do not feel that this review provides a fully accurate and up to date summation of the current evidence base for using cryotherapy in acute injury management.

  Primarily, the review fails to include a list of reasons for excluding potential studies. This does not follow the recommendations of the Quality of Reporting of Meta-Analysis (QUORUM) Statement1 which highlight the importance of providing the number of trials identified, included and excluded, along with the reasons for exclusion when carrying out a systematic review. This process ensures that study selection is both systemic and reproducible. However, a simple literature search reveals a number of studies that seem to fulfil the inclusion criteria set out in Collins (2008) review; yet have not been included, and it is difficult for the reader to ascertain why.

  It seems there are also a number of serious issues with the methodological quality scores. The most pertinent issue is that in three studies, the final PEDro scores do not concur with the ratings given by PEDro project officers (www.pedro.fhs.usyd.edu.au). Best practice should be to use two blinded researchers to rate each study, with differences resolved by consensus discussion. As this was not undertaken in the current study, it may explain some of the inaccuracies. In one case, an included study2 is described as ‘well designed’, when it is clearly lacks: adequate baseline comparability, allocation concealment, follow up, intention to treat analysis and a simple measure of variability such as a standard deviation.

  There was no structured assessment of the design of the two included systematic reviews, and the critiques may be very subjective. The author states that one of the systematic reviews (which included randomised controlled trials (RCT’s) using injured human subjects) employed inclusion criteria that was too broad, and therefore resulted in a non-specific conclusion. A similar criticism may be levelled at the current paper given that Collin’s review (2008) included: animal studies, non randomised studies on injured humans, RCT’s, and systematic reviews. This is an extremely heterogeneous sample of included studies that range from: a well -designed RCT of injured humans using a four week follow up3; to a small- unblinded study on 16 piglets with a laboratory induced crush injury.4

  The author poses the question that ‘If cryotherapy was a pharmacological therapy, is there an evidence base to support its use?’ This is an excellent question that raises a number of important issues; unfortunately, this review missed the opportunity to discuss them. It is common knowledge that one of the key components in ensuring effectiveness and safety of pharmacological agents is determining an optimal dosage. An intervention such as cryotherapy is no different; and perhaps one of the reasons why the author concludes that ‘there is insufficient evidence base for cryotherapy’, is due to the paucity of studies which used a clinically effective intervention. For example, the majority of studies included in Collins (2008) review, used single cryotherapy applications. Would we expect a single application to have a clinically significant therapeutic effect? And indeed, does this reflect current clinical practice? Before we use systematic reviews to make judgements on the effectiveness of an intervention, we must ensure primarily that the methods of the review are completed with rigor. Furthermore, we must not only review and rate the methodological quality of the evidence base, but the clinical effectiveness of the interventions used. A recent well-designed review5 used this approach to highlight that other electro-physical interventions can be effective in treating soft tissue injury, provided that optimal treatment dosage is used.

  In light of this, and the aforementioned methodological shortcomings, the final conclusions that are made, may be questionable. Collins (2008) concludes that cryotherapy may be of benefit if it is instituted soon after the injury and care is taken to limit the exposure time and to induce only modest cooling. It is difficult to determine what these recommendations are based on as the included studies do little to define what ‘modest’ cooling is, or indeed how we can achieve this clinically.

  Reference: 1. Moher D, Cook DJ, Eastwood S, Olkin I, Rennie D, Stroup DF: Improving the quality of reports of meta-analysis of randomised controlled trials: the QUORUM statement. The Lancet 1999, 354: 1896-1900.

  2. Sloan JP, Hain R, Pownall R. (1989). Clinical benefits of early cold therapy in accident and emergency following ankle sprain. Archives of Emergency Medicine 1989; 6: 1-6.

  3. Airaksinen OV, Kyrklund N, Latvala K, Kouri JP, Gronblad M, Kolari P. Efficacy of cold gel for soft tissue injuries: a prospective randomised double blinded trial. Am J Sports Med 2003: 31: 680-4

  4. Farry PJ, Prentice NG, Hunter AC, Wakelin CA. Ice treatment of injured ligaments: an experimental model. NZ Medical Journal 1980; 91: 12- 14.

  5. Bjordal JM, Johnson MI, Lopes-Martins RA, Bogen B, Chow R, Ljunggren AE. Short term efficacy of physical interventions in osteoarthritic knee pain. A systematic review and meta-analysis of randomised placebo controlled trials. BMC Musculoskelet Disord 2007 22: 8: 51

  Show Less

  Conflict of Interest:
  None declared.

  • Back to top
• Published on: 29 April 2016

  Ice / Cryotherapy and STI managment

  • Stephen H Boyce

  I read with interest NC Collins review article regarding the use of ice in the management of acute soft tissue injuries (STI). The conclusion, that there is insufficient evidence to suggest the use of ice / cryotherapy improves clinical outcome. NC Collins highlights one the main problems within sports injury / STI management - that many of the accepted clinical practices that are used have little solid evidence base behin...

  Show More

  I read with interest NC Collins review article regarding the use of ice in the management of acute soft tissue injuries (STI). The conclusion, that there is insufficient evidence to suggest the use of ice / cryotherapy improves clinical outcome. NC Collins highlights one the main problems within sports injury / STI management - that many of the accepted clinical practices that are used have little solid evidence base behind their rationale.

  There are many problems in conducting a randomised controlled trial regarding the use of ice in an acute STI. -Time from injury to presentation is variable and patients may be included up to 72 hours post-injury where swelling may have an effect on clinical outcome. -Patients may also have applied ice to their injury in the pre-hospital setting thus excluding themselves from any possible randomisation. -Any icing protocol will rely heavily upon the patients rigid compliance. -Blinding of patients to the use of ice is not possible and pre-conceived ideas about the benefits of ice may influence results especially when subjective outcome measures are used. -Outcomes measures are difficult to quantify and are often subjective in nature, ie, ankle function scales, pain scoring scales. -How to differentiate the effect of ice alone or in combination with other elements of RICE, mainly compression and elevation.

  A recent study by Bleakely et al in the British Journal of Sports Medicine (1) compared two icing protocols in the managment of acute ankle sprains. The results highlighted only a small difference in ankle pain on activity after one week when ice was applied intermittently. Although they did not find any difference in many other outcomes analysed, the study was underpowered and it is possible that further studies may demonstrate a difference.

  Until definative evidence is present otherwise in the literature the use of ice in acute STI management will continue. Many sports physicians will give anecdotal testament to the benefits of cryotherapy and use ice in the immediate management of STI. I would even suspect that if cryotherapy was proven to be off no benefit in the future, sportsmen would still want to use ice for their injuries, sports physicians would be reluctant not to use ice and many years would pass before this practice changed.

  References: (1) Bleakley CM, McDonough SM, MacAuley DC. Cryotherapy for acute ankle sprains: A randomised controlled study of two different icing protocols. Br J Sports Med 2006;40:700-705.

  Show Less

  Conflict of Interest:
  None declared.

  • Back to top