Safety evaluation of secondary conversion from external fixation to internal fixation for open tibia fractures

目的: 评估开放性胫骨骨折自外支架更换为内固定的安全性。. Methods: Between January 2010 and December 2014, 94 patients (98 limbs) with open tibia fractures were initially treated with external fixators at the first stage, and the clinical data were retrospectively analyzed. In 29 cases (31 limbs), the external fixators were changed to internal fixation for discomfort, pin tract response, Schantz pin loosening, delayed union or non-union after complete wound healing and normal or close to normal levels of erythrocyte sedimentation rate (ESR), C reactive protein (CRP), and the leucocyte count as well as the neutrophil ratio (trial group); in 65 cases (67 limbs), the external fixators were used as the ultimate treatment in the control group. There was no significant difference in gender, age, side of the limbs, interval from injury to the first debridement, initial pathogenic bacteria, the limbs that skin grafting or flap transferring for skin and soft tissue defect between the two groups ( P>0.05). The incidence of Gustilo type III fractures in the control group was significantly higher than that in the trial group ( P=0.000). The overall incidence of infection was calculated respectively in the two groups. The incidence of infection according to different fracture types and whether skin grafting or flap transferring was compared between the two groups. The information of the pathogenic bacteria was recorded in the infected patients, and it was compared with the results of the initial culture. The incidence of infection in the patients of the trial group using different internal fixation instruments was recorded. 结果: 试验组和对照组总体感染发生率分别为 9.7%（3/31）和 9.0%（6/67），比较差异无统计学意义（ χ2=0.013， P=0.909）。Ⅰ、Ⅱ型患者均未发生感染；试验组和对照组ⅢA 型患者感染发生率分别为 14.3%（1/7）和 6.3%（2/32），ⅢB 型分别为 50.0%（2/4）和 14.3%（2/14），ⅢC 型分别为 0 和 16.7%（2/12），比较差异均无统计学意义（ χ2=0.509， P=0.476； χ2=2.168， P=0.141； χ2=0.361， P=0.548）。发生感染的患肢中，仅试验组 1 侧金黄色葡萄球菌与术前原始致病菌一致。接受植皮或皮瓣移位手术的患者中，试验组和对照组感染发生率分别为 33.3%（2/6）和 13.3%（2/15），比较差异无统计学意义（ χ2=1.059， P=0.303）。试验组更换为内固定后，采用髓内钉者（11 侧）无 1 例发生感染，而采用钢板（20 侧）的患者中 4 侧发生感染，感染发生率为 20%。. 结论: 多数情况下，开放性胫骨骨折患者自外支架更换为内固定是安全的。但针对初始创伤伴广泛而严重软组织损伤者，特别是 GustiloⅢ型骨折且通过皮瓣或植皮修复获得创面愈合者，术前必须仔细评估患者软组织条件，谨慎选择内固定物类型，术中对软组织进行精细保护。.