To compare and explore the clinical effectiveness of two-step or one-step transplantation reconstruction using Lando^? artificial dermis combined with autologous split-thickness skin graft (STSG) for wounds with deep soft tissue defects.

From January 2021 to June 2022, 74 patients with deep defects of skin soft tissue were treated in three hospitals including Nanfang Hospital of Southern Medical University, Ganzhou Municipal hospital and First Affiliated Hospital of Naval Medical University. They were randomly divided into one-step method group and two-step method group according to the random number table method. The experimental group was one-step method group and the control group was two-step method group, with 37 cases in each group. In one-step method group, Lando^? artificial dermis was perfomed with STSG simultaneously, including 27 males and 10 females aged 27 (19.5, 53.5) with 15 cases of burn scar resection wounds, 9 cases of plastic wounds, and 13 cases of trauma wounds. In two-step method group, Lando^? artificial dermis was performed in the first stage, followed by autologous split-thickness skin grafting in the second stage, including 25 males and 12 females aged 36 (22.5, 56.5) with 15 cases of burn scar resection wounds, 11cases of plastic wounds, and 11 cases of trauma wounds. The main efficacy index was skin graft survival rate, and the secondary efficacy indexes were infection rate, length of hospital stay, and 3-month-postoperation Vancouver Scar Scale score (VSS score). The data were compared by Chi-square test, Fisher exact probability test, t test or Mann-Whitney U test. The data of the main efficacy index was tested by the non-inferiority hypothesis.

Statistical data was compared between one-step method group and two-step method group. The main efficacy index of the survival rate of skin graft was (94.32±8.38)% vs. (95.86±6.40)%, and the lower limit of the 95% confidence interval of the difference between the two groups of skin graft survival rate was less than the non-inferiority margin. The main efficacy index of the one-step method group was non-inferior to the two-step method group. The secondary efficacy index of the infection rate was 2.71% vs. 8.11%, the length of hospital stay was (18.11±2.50) d vs. (26.32±3.50) d, and the VSS score at three months after operation was (3.97±1.15) points vs. (3.94±1.11) points. Except for the significant difference in hospital stay (t=-11.605, P=0.000), there was no significant difference in both infection rate and VSS score (P>0.05). For patients with burn scar resection surgery, there was significant difference between pre-operative VSS score and post-operative VSS score at three months in both one-step method group and two-step method group (t=9.333、13.342, P=0.000、0.000).

Lando^? artificial dermis combined with split-thickness skin graft is used to repair wounds by two-step or one-step method, and the one-step method is non-inferior to the two-step method in the survival rate of skin graft, the conclusion of non-inferiority is established. Both methods can significantly inhibit scar hyperplasia, and the repair effect is good. Compared with the two-step transplantation repair, the one-step transplantation repair can significantly shorten the hospitalization time of patients. Therefore, one-step transplantation can be widely used in clinics for wounds with good blood supply.