A prospective study on the expansion rule of the directional skin and soft tissue expander in abdominal scar reconstruction / 中华烧伤杂志

ABSTRACT

Objective: To observe the expansion rule of directional skin and soft tissue expander (hereinafter referred to as expander) in abdominal scar reconstruction. Methods: A prospective self-controlled study was conducted. Twenty patients with abdominal scar who met the inclusion criteria and admitted to Zhengzhou First People's Hospital from January 2018 to December 2020 were selected by random number table method, including 5 males and 15 females, aged 12-51 (31±12) years, with 12 patients of type Ⅰ scar and 8 patients of type Ⅱ scar. In the first stage, two or three expanders with rated capacity of 300-600 mL were placed on both sides of the scar, of which at least one expander had rated capacity of 500 mL (as the follow-up observation object). After the sutures were removed, water injection treatment was started, with the expansion time of 4 to 6 months. After the water injection volume reached 2.0 times of the rated capacity of expander, abdominal scar excision+expander removal+local expanded flap transfer repair was performed in the second stage. The skin surface area at the expansion site was measured respectively when the water injection volume reached 1.0, 1.2, 1.5, 1.8, and 2.0 times of the rated capacity of expander, and the skin expansion rate of the expansion site at corresponding multiples of expansion (1.0, 1.2, 1.5, 1.8, and 2.0 times) and adjacent multiple intervals (1.0-1.2, 1.2-1.5, 1.5-1.8, and 1.8-2.0 times) were calculated. The skin surface area of the repaired site at 0 (immediately), 1, 2, 3, 4, 5, and 6 months after operation, and the skin shrinkage rate of the repaired site at different time points (1, 2, 3, 4, 5, and 6 months after operation) and different time periods (0-1, 1-2, 2-3, 3-4, 4-5, and 5-6 months after operation) were calculated. Data were statistically analyzed with analysis of variance for repeated measurement and least significant difference-t test. Results: Compared with the expansion of 1.0 time ((287.6±2.2) cm2 and (47.0±0.7)%), the skin surface area and expansion rate of the expansion site of patients ((315.8±2.1), (356.1±2.8), (384.9±1.6), and (386.2±1.5) cm2, (51.7±0.6)%, (57.2±0.6)%, (60.4±0.6)%, and (60.5±0.6)%) were significantly increased when the expansion reached 1.2, 1.5, 1.8, and 2.0 times (with t values of 46.04, 90.38, 150.14, 159.55, 45.11, 87.83, 135.82, and 118.48, respectively, P<0.05). Compared with the expansion of 1.2 times, the skin surface area and expansion rate of the expansion site of patients were significantly increased when the expansion reached 1.5, 1.8, and 2.0 times (with t values of 49.82, 109.64, 122.14, 144.19, 49.51, and 105.85, respectively, P<0.05). Compared with the expansion of 1.5 times, the skin surface area and expansion rate of the expansion site of patients were significantly increased when the expansion reached 1.8 times (with t values of 38.93 and 39.22, respectively, P<0.05) and 2.0 times (with t values of 38.37 and 38.78, respectively, P<0.05). Compared with the expansion of 1.8 times, the skin surface area and expansion rate of the expansion site of patients both had no statistically significant differences when the expansion reached 2.0 times (with t values of 4.71 and 4.72, respectively, P>0.05). Compared with the expansion of 1.0-1.2 times, the skin expansion rate of the expansion site of patient was significantly increased when the expansion reached 1.2-1.5 times (t=6.95, P<0.05), while the skin expansion rate of the expansion site of patient was significantly decreased when the expansion reached 1.5-1.8 and 1.8-2.0 times (with t values of 5.89 and 40.75, respectively, P<0.05). Compared with the expansion of 1.2-1.5 times, the skin expansion rate of the expansion site of patient was significantly decreased when the expansion reached 1.5-1.8 and 1.8-2.0 times (with t values of 10.50 and 41.92, respectively, P<0.05). Compared with the expansion of 1.5-1.8 times, the skin expansion rate of the expansion site of patient was significantly decreased when the expansion reached 1.8-2.0 times (t=32.60, P<0.05). Compared with 0 month after operation, the skin surface area of the repaired site of patient at 1, 2, 3, 4, 5, and 6 months after operation was significantly decreased (with t values of 61.66, 82.70, 96.44, 102.81, 104.51, and 102.21, respectively, P<0.05). Compared with 1 month after operation, the skin surface area of the repaired site of patient was significantly decreased at 2, 3, 4, 5, and 6 months after operation (with t values of 37.37, 64.64, 69.40, 72.46, and 72.62, respectively, P<0.05), while the skin shrinkage rate was significantly increased (with t values of 32.29, 50.00, 52.67, 54.76, and 54.62, respectively, P<0.05). Compared with 2 months after operation, the skin surface area of the repaired site of patient was significantly decreased at 3, 4, 5, and 6 months after operation (with t values of 52.41, 60.41, 70.30, and 65.32, respectively, P<0.05), while the skin shrinkage rate was significantly increased (with t values of 52.97, 59.29, 69.68, and 64.50, respectively, P<0.05). Compared with 3 months after operation, the skin surface area of the repaired site of patient was significantly decreased at 4, 5, and 6 months after operation (with t values of 5.53, 38.00, and 38.52, respectively, P<0.05), while the skin shrinkage rate was significantly increased (with t values of 25.36, 38.59, and 37.47, respectively, P<0.05). Compared with 4 months after operation, the skin surface area (with t values of 41.10 and 50.50, respectively, P>0.05) and skin shrinkage rate (with t values of 48.09 and 50.00, respectively, P>0.05) of the repaired site of patients at 5 and 6 months after operation showed no statistically significant differences. Compared with 5 months after operation, the skin surface area and skin shrinkage rate of the repaired site of patient at 6 months after operation showed no statistically significant differences (with t values of 9.40 and 9.59, respectively, P>0.05). Compared with 0-1 month after operation, the skin shrinkage rate of the repaired site of patient at 1-2, 2-3, 3-4, 4-5, and 5-6 months after operation was significantly decreased (with t values of 13.56, 40.00, 49.21, 53.97, and 57.68, respectively, P<0.05). Compared with 1-2 months after operation, the skin shrinkage rate of the repaired site of patients at 2-3, 3-4, 4-5, and 5-6 months after operation was significantly decreased (with t values of 12.37, 27.72, 30.16, and 31.67, respectively, P<0.05). Compared with 2-3 months after operation, the skin shrinkage rate of the repaired site of patients at 3-4, 4-5, and 5-6 months after operation was significantly decreased (with t values of 33.73, 41.31, and 54.10, respectively, P<0.05). Compared with 3-4 months after operation, the skin shrinkage rate of the repaired site of patient at 4-5 and 5-6 months after operation showed no statistically significant differences (with t values of 10.90 and 23.60, respectively, P>0.05). Compared with 4-5 months after operation, the skin shrinkage rate of the repaired site of patient at 5-6 months after operation showed no statistically significant difference (t=20.90, P>0.05). Conclusions: The expander can effectively expand the abdominal skin, thus repairing the abdominal scar deformity. Maintained expansion for one month after the water injection expansion reaches 1.8 times of the rated capacity of the expander can be set as a phase Ⅱ operation node.