The Effect of Cold Air Application for the Intraarticular and Skin Temperature Changes of Knees

The purposes of this study are to investigate the effect of the cold air application in the skin and intraarticular temperature changes and to observe the rebound temperature changes after cooling. We recorded the changes of the skin surface and intraarticular temperatures of knees during and after the cold air application. The intraarticular temperature was measured by a temperature probe inserted into the knee joint cavity and the skin temperature by the infrared system. Eighteen healthy subjects were examined. The knee was cooled by a 5-minutes application of CRAis (Kyung-won Century, Korea) machine and the intraarticular and skin temperatures of knees were measured at every 0.5-minute during and after the cold therpy, then at every minute for 5 minutes, and every 5-minute for the next 110 minutes. We also evaluated the variables that might affect the skin and intraarticular temperature changes. Results showed that the mean skin temperature dropped from 31.8oC to 10.5oC immediately after the cold air application for 5-minutes. The mean intraarticular temperature dropped from 33.9oC to 30.0oC after the cold air application for 5-minutes. Two hours after the initiation of treatment with cold air, the mean intraarticular temperatures did not recover to the baseline values(p<0.01). No significant correlations were found between the body mass index with the intraarticular and surface temperatures of knees. A highly significant correlation was noted between the baseline skin surface and intraarticular temperatures(p<0.01). In conclusion, the reduction of the joint temperature by the cold air application using CRAis machine can be a useful treatment method for the synovitis of knees.

The Location of the Center of Pressure in Foot during Stance Phase of Normal Gait by Plantar Pressure Measurement

The purpose of this study was to detect where the center of pressure in foot would be located at the end point of loading response and the terminal stance by the dynamic plantar pressure measurement. Seventeen adults who had the usual feet without a pathologic gait were evaulated simultaneously by the motion analysis using VICON 370, and the plantar pressure measurement using EMED-SF. Two devices were set in the 60 Hz frame. The foot was divided into 3 different zones; hindfoot, midfoot, and forefoot. The end point of loading response was located at the 1.92+/-1.46 frame distal to the hindfoot- midfoot borderline. The end point of terminal response was located at the 2.27+/-1.96 frame distal to the maximal pressure points of metatarsal head. Authors could differentiate each period of stance phase; the initial contact, loading response, mid-stance, terminal stance, and preswing, using the analysis of center of pressure by the dynamic plantar pressure measurement.

The Effect of Cold Air Application on the Intramuscular and the Skin Surface Temperatures in the Gluteal Muscle

Purpose of this study is to evaluate the temperature lowering effects of the local cold air application on the skin surface and the muscle of different depth, and to observe whether the rebound rise of the temperature occurs after the cold air application. Subjects were prepared in a relaxed prone position. Cold air of CRAis(Kyung-won Century, Korea) was applied to the gluteal area of 20 healthy subjects for 5 minutes. The skin and intramuscular temperatures were measured by a thermogram(Infrared system, Sweden) and digital thermometers(Barnant company, USA). The temperatures were measured before and 30 seconds after the cold air application, and then every 5 minutes for the next 110 minutes. The few variables were considered that might affect the temperature changes. The thermometer-probes were inserted into the outer quadrant of the gluteal muscle below 5 cm from the iliac crest with the depth of 2 cm, 4 cm, and 6 cm respectively. ANOVA was used for the analysis of the data. The resting temperature of the skin surface was 32.6+/-1.2oC, and the lowest temperature was 12.9+/-3.3oC after 5 minutes of cold air application. The resting intramuscular temperatures with 2 cm, 4 cm, and 6 cm depth were 36.5+/-0.2oC, 36.9+/-0.2oC, and 37.1+/-0.2oC respectively (p<0.05). The lowest temperature in 2 cm, 4 cm, and 6 cm depth was 35.1+/-0.7oC, 36.2+/-0.4oC, and 36.9+/-0.3oC respectively(p<0.05). The mean duration to reach the lowest temperature was 20, 25, and 45 minutes respectively. The temperatures in the skin and the muscle with the depth of 2 cm, 4 cm, and 6 cm after 2 hours on cold air application were 32.2+/-1.1oC, 36.2+/-0.5oC, 36.6+/-0.3oC, and 36.9+/-0.3oC(p<0.05) respectively. The temperatures in the skin and the muscle were significantly lower after 2 hours than before the cold air application(p<0.05). The change of skin surface temperature was more rapid than that of the muscle and the deeper the muscle was the lesser the temperature change. In conclusion, the effect of cold air application for 5 minutes lasts up to 2 hours and the rebound rise of the temperature due to reactive vasodilatation seems not to occur in the gluteal muscle.