The effect of topical anti blister products on the risk of friction blister formation on the foot.

INTRODUCTION: Foot blisters are a common injury, which can impact on activity and lead to infection. Increased skin surface hydration has been identified as a risk factor for blister formation, indicating that a reduction in hydration could reduce the risk of blister. METHOD: Thirty healthy adults were randomised into 3 groups, each receiving a preventative foot blister treatment (2Toms(®) Blister Shield(®); Flexitol(®) Blistop and Boots Anti-Perspirant Foot Spray). Cycles of compression and shear loads where applied to heel skin using a mechanism driven by compressed air. Temperature changes were measured during load application using a thermal imaging camera (FLIR Systems Inc. and Therm CAM™ Quick Report). Near surface hydration of the skin was measured using a Corneometer(®) (C & K, Germany). RESULTS: There was no significant difference in the rate of temperature change of the skin between the three groups compared to not using products (p = 0.767, p = 0.767, p = 0.515) or when comparing each product (p = 0.551). There was a significant decrease in near surface skin hydration, compared to baseline, after the application of powder (-8.53 AU, p = 0.01). There was no significant difference in hydration after the application of film former and antiperspirant (-1.47 AU, p = 0.26; -1.00 AU, p = 0.80, respectively). CONCLUSION: With the application of external load we found no significant difference in the effect of the three products on temperature change. The powder product demonstrated an effect on reducing the risk of blister. It is postulated that powder may have a barrier effect.

The effect of hydration on the risk of friction blister formation on the heel of the foot.

BACKGROUND: Friction blister research has focused on prevention and treatment approaches rather than exploring the pathophysiology of the friction blister. Increased skin hydration has been purported to be a key risk factor in friction blister development. This study aimed to test the effect of increased skin surface hydration on the risk of friction blister creation. METHODS: The skin on one foot was hydrated by soaking the foot in water. Intermittent loading was carried out until an observable change of 3°C was evident using infrared thermography. The contra lateral foot acted as a control. Skin hydration and elasticity was measured using electrical capacitance and negative pressure respectively. RESULTS: The rate of temperature change of the hydrated group was significantly greater than that of the non-hydrated foot group (P = 0.001) and showed a strong positive correlation (r = 0.520) with skin surface hydration. Weak negative correlations were seen between skin elasticity and rate of temperature change in response to load application (r = -0.166) and skin surface hydration and elasticity at baseline (r = -0.195). CONCLUSION: In controlled experimental conditions increased skin surface hydration increases the rate of temperature change of the skin in response to load application and consequently increases the risk of blister creation.