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.
目的： 观察定向皮肤软组织扩张器（以下简称扩张器）在腹部瘢痕整复中的扩张规律。方法： 采用前瞻性自身对照研究方法。采用随机数字表法选择2018年1月—2020年12月郑州市第一人民医院收治的20例符合入选标准的腹部瘢痕患者，其中男5例、女15例，年龄12~51（31±12）岁，Ⅰ型瘢痕患者12例、Ⅱ型瘢痕患者8例。Ⅰ期在瘢痕两侧置入额定容量为300~600 mL的扩张器2或3枚，其中至少1枚额定容量为500 mL（作为后续观察对象）。拆线后开始注水治疗，扩张时间为4~6个月，注水量达扩张器额定容量2.0倍后，Ⅱ期行腹部瘢痕切除+扩张器取出+局部扩张皮瓣转移修复。分别测定注水量达扩张器额定容量1.0、1.2、1.5、1.8、2.0倍时扩张处的皮肤表面积，并计算扩张相应倍数（1.0、1.2、1.5、1.8、2.0倍）和相邻倍数区间（1.0~1.2、1.2~1.5、1.5~1.8、1.8~2.0倍）时扩张处的皮肤扩张率；测定术后0（即刻）、1、2、3、4、5、6个月时修复处的皮肤表面积，并计算术后不同时间点（术后1、2、3、4、5、6个月）和术后不同时间段（术后0~1、1~2、2~3、3~4、4~5、5~6个月）修复处的皮肤回缩率。对数据行重复测量方差分析、LSD-t检验。结果： 与扩张1.0倍［（287.6±2.2）cm2、（47.0±0.7）%］比较，扩张1.2、1.5、1.8、2.0倍时患者扩张处的皮肤表面积和扩张率［（315.8±2.1）、（356.1±2.8）、（384.9±1.6）、（386.2±1.5）cm2，（51.7±0.6）%、（57.2±0.6）%、（60.4±0.6）%、（60.5±0.6）%］均明显增加（t值分别为46.04、90.38、150.14、159.55，45.11、87.83、135.82、118.48，P<0.05）；与扩张1.2倍比较，扩张1.5、1.8、2.0倍时患者扩张处的皮肤表面积和扩张率均明显增加（t值分别为49.82、109.64、122.14，144.19、49.51、105.85，P<0.05）；与扩张1.5倍比较，扩张1.8倍（t值分别为38.93、39.22，P<0.05）、2.0倍（t值分别为38.37、38.78，P<0.05）时患者扩张处的皮肤表面积和扩张率均明显增加；与扩张1.8倍比较，扩张2.0倍时患者扩张处的皮肤表面积和扩张率差异均无统计学意义（t值分别为4.71、4.72，P>0.05）。与扩张1.0~1.2倍比较，扩张1.2~1.5倍时患者扩张处的皮肤扩张率明显增加（t=6.95，P<0.05），扩张1.5~1.8、1.8~2.0倍时患者扩张处的皮肤扩张率均明显降低（t值分别为5.89、40.75，P<0.05）；与扩张1.2~1.5倍比较，扩张1.5~1.8、1.8~2.0倍时患者扩张处的皮肤扩张率均明显降低（t值分别为10.50、41.92，P<0.05）；与扩张1.5~1.8倍比较，扩张1.8~2.0倍时患者扩张处的皮肤扩张率明显降低（t=32.60，P<0.05）。与术后0个月比较，术后1、2、3、4、5、6个月患者修复处的皮肤表面积均明显减少（t值分别为61.66、82.70、96.44、102.81、104.51、102.21，P<0.05）；与术后1个月比较，术后2、3、4、5、6个月患者修复处的皮肤表面积均明显减少（t值分别为37.37、64.64、69.40、72.46、72.62，P<0.05）、回缩率均明显增加（t值分别为32.29、50.00、52.67、54.76、54.62，P<0.05）；与术后2个月比较，术后3、4、5、6个月患者修复处的皮肤表面积均明显减少（t值分别为52.41、60.41、70.30、65.32，P<0.05）、回缩率均明显增加（t值分别为52.97、59.29、69.68、64.50，P<0.05）；与术后3个月比较，术后4、5、6个月患者修复处的皮肤表面积均明显减少（t值分别为5.53、38.00、38.52，P<0.05）、回缩率均明显增加（t值分别为25.36、38.59、37.47，P<0.05）；与术后4个月比较，术后5、6个月患者修复处的皮肤表面积（t值分别为41.10、50.50，P>0.05）和回缩率（t值分别为48.09、50.00，P>0.05）差异均无统计学意义；与术后5个月比较，术后6个月患者修复处的皮肤表面积和回缩率差异均无统计学意义（t值分别为9.40、9.59，P>0.05）。与术后0~1个月比较，术后1~2、2~3、3~4、4~5、5~6个月患者修复处的皮肤回缩率均明显降低（t值分别为13.56、40.00、49.21、53.97、57.68，P<0.05）；与术后1~2个月比较，术后2~3、3~4、4~5、5~6个月患者修复处的皮肤回缩率均明显降低（t值分别为12.37、27.72、30.16、31.67，P<0.05）；与术后2~3个月比较，术后3~4、4~5、5~6个月患者修复处的皮肤回缩率均明显降低（t值分别为33.73、41.31、54.10，P<0.05）；与术后3~4个月比较，术后4~5、5~6个月患者修复处的皮肤回缩率差异均无统计学意义（t值分别为10.90、23.60，P>0.05）；与术后4~5个月比较，术后5~6个月患者修复处的皮肤回缩率差异无统计学意义（t=20.90，P>0.05）。结论： 扩张器能有效扩张腹部皮肤，从而修复腹部瘢痕畸形，注水扩张达扩张器额定容量1.8倍后维持扩张1个月，可以作为Ⅱ期手术时间节点。.