Effects of Different Cryotherapy Techniques on Skin Surface Temperature, Agility and Balance Comparison Between Cold Water Immersion, Game Ready ® , And Ice Pack: A Randomised Clinical Trial

Effects of Different Cryotherapy Techniques on Skin Surface Temperature, Agility and Balance - Comparison Between Cold Water Immersion, Game Ready ® And Ice Pack: A Randomised Clinical Trial. Biomed J Sci & Tech Res 39(1)-2021. BJSTR. MS.ID.006250. Problem Statement: Cryotherapy is widely used for the treatment of acute soft tissue lesion, however, its results are directly associated with the technique used. Approach: To establish differences between the application of cryotherapy techniques on the ankle joint. Purpose: This is a randomized clinical trial. Twenty young and physically active participants (10 men and 10 women) participated in the study. The analysis of superficial skin temperature (SST) of the anterior, lateral, and posterior regions of the ankle, agility performance, and dynamic balance after the application of cold water immersion (CWI), cryotherapy+Game Ready® compression (CGRC), or ice pack (IP) was performed. Rewarming and agility and balance performance were analyzed up to 30 minutes after interventions. Results: The CWI demonstrated lower SST (p<0.01) for all regions of the ankle; followed by the CGRC and IP. The CWI and CGRC provided better cooling up to 30 minutes (p<0.01) in the anterior region of the ankle. The CWI and CGRC groups showed greater cooling of the posterior region of the ankle up to 10 minutes (p=0.02). The CWI group performed worst in agility. No changes were observed in dynamic balance. Conclusions: The CWI and CGRC groups performed better in decreasing SST in all regions of the ankle. The CWI group demonstrated reduced agility performance. Dynamic balance was not altered. These results may contribute to the choice of the best cryotherapy technique, to be used in clinical practice as recovery after exercise or for treatment of acute injuries.


Introduction
Cryotherapy is widely used for the treatment of acute soft tissue [1] to reduced pain, slow edema formation, decreased tissue temperature and cell permeability, induced superficial vasoconstriction, and prevention of secondary hypoxic injury [2,3].
However, its results are directly associated with the technique used, application time, decrease in skin temperature, and depth of cold penetration [4]. Among the cryotherapy techniques the ice pack is a low-cost device which is easily accessible, causing a reduction in tissue temperature and physiological changes to at least one centimeter [5,6], the cold water immersion (CWI) allows a greater DOI: 10.26717/BJSTR.2021.39.006250 body area to be exposed to cold [7], maintaining tissue cooling for longer and providing increased analgesia [8] and cryotherapy with intermittent compression can deliver similar results [9,10]. The literature shows that cryotherapy with intermittent compression is widely used for recovery of ligament injuries [11], total knee arthroplasty [12] and reduction in post-operative pain [10].
This form of application is effective in reducing pain [10,13,14], improving tissue oxygenation and microcirculation, and providing faster recovery from ligament disorders [15]. In addition, Murgier at. al. Murgier, et al. [11] reported that pneumatic compression and cryotherapy may reduce pain and postoperative blood loss, and lead to higher functional scores [12]. On the other hand, cryotherapy and intermittent compression equipment are more expensive and less accessible for health professionals. Several studies have aimed to evaluate the differences between the application of cryotherapy techniques, with divergent methods and contradictory results [10,16,17]. In addition, Hawkins and Hawkins [18] reported that sports physical therapists applied cryotherapy with great variability for acute or sub-acute ankle sprain and that efforts need to be made to substantiate the evidence of cryotherapy application [19].
Thus, little is known about the differences between the applications of an ice pack, cold water immersion, and cryotherapy associated with intermittent compression for the purpose of reducing skin surface temperature (related to treatment efficacy) and changing agility and balance. Therefore, new research should include controlled and reproducible different techniques. To contribute to discussions on the effects and indications of different techniques of cryotherapy on the ankle joint, the present study aimed to establish differences between applications of cryotherapy techniques on the ankle superficial skin temperature (SST) in different regions of this joint; the effects on agility and dynamic balance were also evaluated. We hypothesized that the three cryotherapy techniques studied would have the same effects on decreasing skin temperature, agility and balance. In addition, we hypothesized that the anterior, posterior, and lateral regions of the ankle would present different values of cooling. Thus, the results may support clinical decision making and aid choices made according to preference among the techniques.

Methods
This was a randomized clinical study, approved by the Research Ethics Committee of the institution (case N. 2.117.378) and registered at www.clinicaltrials.gov (ID NCT03659474). All procedures were performed at the physiotherapy outpatient clinic of the University. Twenty young and physically active subjects (ten men and ten women), without injuries or complaints in the ankle participated in the study. The women's evaluations were carried out outside the menstrual period, since when they are menstruating, worsening in agility and dynamic balance can occur [20]. The sample size was calculated based on the results of the manuscript "The Magnitude of Tissue Cooling during Cryotherapy with Varied Types of Compression" [21], considering the SST over In sequence, the Y test and Side Hop Test (SHT) were developed, already used in previous studies for the analysis of dynamic balance (22,23) and agility (24), respectively. Participants were familiarized with the tests prior to conducting the data collection.
After the baseline assessment, the participants performed a warm-up with a 15-minute walk on the treadmill (Movement®) at a constant and comfortable pace. Immediately after walking, subjects were referred to one of three cryotherapy techniques for testing.
For the CWI group, the ankle joint was immersed in cold water up to the mid portion of the tibia, at approximately 4°C [22], controlled by the thermal camera. For the CGRC group, the ankle joint was   in the final assessment [23]. The average of the SDs was calculated through the arithmetic mean of the standard deviations related to the initial and final assessments: (SD1+ SD2)/2. The effect size was defined as ≤ 0.5 representing a small effect, between >0.5 and ≤ 0.8, a medium effect, and > 0.8, a large effect [23].

Results
Twenty physically active subjects (10 men (Table 1), related to analgesic effects [24]. The comparisons between the three application techniques showed that the CWI induced lower SST values for the anterior and lateral regions of the ankle at up to 10 minutes after application.

Discussion
The The best results associated with CWI application can be explained by the greater cooling area of contact [7], the hydrostatic pressure that redirected the skin blood flow to the central circulation [27], and the local vasoconstriction that reduces the fluid flux into the interstitial space. The intervention with CGRC provided satisfactory results that may be related to cooling associated with compression [12]. The results achieved for the effects of cryotherapy on agility performance, evaluated by SHT, confirmed the findings of previous studies, such as those reported by Macedo, et al. [22] and Furmanek, Słomka, & Juras [28] who showed worse functional performance immediately after CWI application. It has commonly been assumed that reduction in nerve conduction velocity may reduce the sensitivity of the afferent mechanoreceptors and the sensitivity of the muscle spindles with less afferent sensory information, causing damage to both the neuromuscular control and functional performance [4,25,29].
Moreover, Kilby, Molenaar, & Newell [30] and Oba, et al. [31] highlighted that the ankle joint capsule is more superficial than the majority of joints, and therefore, the receptors may be more influenced by cryotherapy application. However, after 10-minutes This finding is important for clinical practice, since CWI application is widely used, low cost, and produced better results for the variables analyzed. For the posterior region of the ankle, CWI and CGRC were similar in cooling, and even at high cost the CGRC is an appropriate choice and can be used according to the preference of the physiotherapist or the patient. In addition, 10 minutes after the application of CWI, agility is worse and greater care must be taken. As limitations of this study it should be pointed out that healthy individuals were evaluated, intramuscular temperature analysis would be more reliable regarding the application of these techniques, and a force platform would be more appropriate to evaluate balance. Further research should complement the results obtained in this study.

Conclusion
The present study concluded that there is a difference in the application of the three cryotherapy techniques. The applications of CWI and CGRC were more effective in cooling and maintaining lower SST of the ankle. These two modalities should be the

Conflict of Interest
None.
Abstract published in Physical Therapy in Sport 31 (2018)

Funding Statement
No funding.