[A prospective randomized controlled study on the repair of skin and soft tissue defect in functional areas of children with full-thickness skin grafts from different sites of abdomen].

Objective: To compare and analyze the effect of repairing small skin and soft tissue defect wounds in functional areas of children with full-thickness skin grafts from different sites of abdomen. Methods: A prospective randomized controlled study was conducted. From January 2019 to June 2020, 60 female children with small skin and soft tissue defects in functional areas requiring full-thickness skin grafting, who met the inclusion criteria, were admitted to the First Affiliated Hospital of Air Force Medical University. According to the random number table, the children were divided into two groups, with 28 cases left in lateral abdomen group aged 5 (3, 8) years and 29 cases in lower abdomen group aged 5 (3, 7) years after the exclusion of several dropped-out children in follow-up. In lower abdomen group, 20 (12, 26) cm2 wounds of children were repaired with (24±10) cm2 full-thickness skin graft from transverse skin lines in the inferior abdomen area, while in lateral abdomen group, 23 (16, 32) cm2 wounds of children were repaired with (24±9) cm2 full-thickness skin graft from below the umbilical plane to above the groin in the lateral abdomen area. All the children were treated with continuous intradermal suture at the donor site incision and received continuous negative pressure treatment of -10.64 to -6.65 kPa in the donor and recipient areas after operation. The donor site was treated with a medical skin tension-reducing closure device since post-surgery day (PSD) 7. The use of medical skin tension-reducing closure device at the donor site, postoperative complications and suture removal time of the donor area were recorded, and the incidence of complications was calculated. On PSD 7, a self-designed efficacy satisfaction questionnaire was used to investigate the parents' satisfaction with the curative effect of their children. In post-surgery month (PSM) 1 and 6, Vancouver scar scale (VSS) was used to evaluate the scar at the donor site, and the VSS score difference between the two time points was calculated; the scar width at the donor site was measured with a ruler, and the scar width difference between the two time points was calculated. Data were statistically analyzed with independent sample t test or Cochran & Cox approximate t test, Mann-Whitney U test, and Fisher's exact probability test. Results: The proportion of children in lateral abdomen group who used the medical skin tension-reducing closure device in the donor area for equal to or more than 4 weeks after surgery was significantly higher than that in lower abdomen group (P<0.05). On PSD 7, there was one case of partial incision dehiscence in the donor area, one case of peripheral skin redness and swelling in the donor area, and one case of fat liquefaction in the donor area in lateral abdomen group, and one case of partial incision dehiscence in the donor area in lower abdomen group. The incidence of postoperative complications at the donor site of children in lower abdomen group was significantly lower than that in lateral abdomen group (P<0.05). Compared with that in lateral abdomen group, the suture removal time at the donor site of children after surgery in lower abdomen group was significantly shorter (t'=17.23, P<0.01). On PSD 7, the satisfaction score of parents with the curative effect of their children in lower abdomen group was significantly higher than that in lateral abdomen group (t'=20.14, P<0.01). In PSM 1 and 6, the VSS scores of scar at the donor site of children in lower abdomen group were 2.7±0.9 and 2.8±1.0, respectively, which were significantly lower than 7.1±2.2 and 9.1±2.7 in lateral abdomen group (with t values of 10.00 and 11.15, respectively, P<0.01). In PSM 6, the VSS score of scar at the donor site of children in lateral abdomen group was significantly higher than that in PSM 1 (t=3.10, P<0.01), while the VSS score of scar at the donor site of children in lower abdomen group was not significantly higher than that in PSM 1 (P>0.05). The VSS score difference of scar at the donor site of children in lateral abdomen group was significantly greater than that in lower abdomen group (Z=-8.12, P<0.01). In PSM 1 and 6, the scar widths at the donor site of children in lower abdomen group were 2.0 (1.0, 2.0) and 2.0 (2.0, 3.0) mm, respectively, which were significantly narrower than 6.0 (4.0, 10.0) and 8.5 (5.0, 12.0) mm in lateral abdomen group (with Z values of -13.41 and -14.70, respectively, P<0.01). In PSM 6, the scar width at the donor site of children in lateral abdomen group was significantly wider than that in PSM 1 (Z=-2.79, P<0.01), while the scar width at the donor site of children in lower abdomen group was not significantly wider than that in PSM 1 (P>0.05). The difference of scar width at the donor site of children in lateral abdomen group was significantly greater than that in lower abdomen group (Z=-14.93, P<0.01). Conclusions: The use of full-thickness skin grafts from the lower abdomen to repair small skin and soft tissue defect wounds in functional areas of children, especially girls, is effective, simple and easy to operate, and conforms to the principle of aesthetic repair. Compared with transplantation with full-thickness skin graft from the lateral abdomen, lower abdominal full-thickness skin grafting has a low incidence of donor site complications and no obvious scar hyperplasia, which is worthy of clinical promotion.