Abstract: Objective To investigate the effects of intermediate frequency therapeutic instrument combined with exposure therapy on blood circulation disorders,collagen synthesis,and skin barrier system after skin flap transplantation in the limbs. Methods Clinical data of 83 patients after skin flap transplantation in the limbs in our hospital from October 2020 to October 2023 were retrospectively collected and categorized into a control group (41 ceses,exposure therapy) and an observation group (42 cases,exposure therapy+intermediate frequency therapeutic instrument) according to the treatment methods. The clinical efficacy,skin flap swelling,pain score,collagen synthesis related indicators,skin barrier system related indicators,wound healing effect and complications of the two groups were statistically analyzed. Results The total effective rate of treatment in the observation group was 92.86%,which was higher than that in the control group (75.61%) (P＜0.05). One week and two weeks after the operation in the observation group, the flap pain was (2.04±0.36) points and (1.33±0.30) points respectively, and the flap swelling scores were (2.22±0.34) points and (1.69±0.31) points respectively. The flap pain scores of the control group at 1 week and 2 weeks after the operation were (3.12±0.40) points and (1.60±0.33) points respectively, and the flap swelling scores were (2.51±0.36) points and (1.87±0.32) points respectively. There was a statistically significant difference between the two groups (P < 0.05).One week after the operation in the observation group, the expression levels of type Ⅰ collagen mRNA and protein in mononuclear cells were 2.56±0.38 and 0.49±0.15 respectively, and the expression levels of type Ⅲ collagen mRNA and protein were 2.89±0.34 and 0.26±0.13 respectively. Two weeks after the operation in the observation group, the expression levels of type Ⅰ collagen mRNA and protein in mononuclear cells were 4.03±0.52 and 0.65±0.16 respectively, and the expression levels of type Ⅲ collagen mRNA and protein were 4.07±0.46 and 0.35±0.15 respectively. One week after the operation, the expression levels of type Ⅰ collagen mRNA and protein in mononuclear cells of the control group were 1.78±0.36 and 0.40±0.14, respectively, and the expression levels of type Ⅲ collagen mRNA and protein were 2.02±0.36 and 0.19±0.12, respectively.Two weeks after the operation, the expression levels of type Ⅰ collagen mRNA and protein in mononuclear cells of the control group were 3.49±0.50 and 0.53±0.20 respectively, and the expression levels of type Ⅲ collagen mRNA and protein were 3.37±0.44 and 0.26±0.20 respectively. There was a statistically significant difference between the two groups (P < 0.05). One week after the operation in the observation group, the sebum secretion volume, stratum corneum water content and pH value were 47.48±4.36, 34.94±4.12 and 5.71±0.23 respectively, and two weeks after the operation, the sebum secretion volume, stratum corneum water content and pH value were 40.21±3.88, 40.12±4.36 and 5.15±0.14 respectively. In the control group, the sebum secretion volume, stratum corneum water content and pH value one week after the operation were 50.53±5.11, 32.03±3.55 and 6.02±0.33 respectively, and the sebum secretion volume, stratum corneum water content and pH value two weeks after the operation were 45.50±4.12, 36.88±4.27 and 5.58±0.20 respectively. There was a statistically significant difference between the two groups (P < 0.05).The number of dressing changes, wound healing time and antibiotic usage time in the observation group were (12.21±2.34) times/month, (12.60±1.87) days and (6.20±1.33) days respectively. The number of dressing changes, wound healing time and antibiotic use time in the control group were (15.58±2.71) times/month, (19.33±2.25) days and (7.68±1.42) days respectively. There was a statistically significant difference between the two groups (P < 0.05). There was no statistically significant difference in blood circulation disorder, wound infection, scar hyperplasia contracture and effusion between the two groups (P > 0.05).Conclusion The effect of intermediate frequency therapeutic instrument combined with exposure therapy in the treatment of skin flap transplantation in the limbs is obvious,which can not only alleviate the degree of postoperative pain and swelling,but also improve collagen synthesis and skin barrier function,which is conducive to postoperative wound healing.

Key words: intermediate frequency therapeutic instrument; exposure therapy; skin flap transplantation; blood circulation disorders; collagen synthesis; skin barrier system