The Experiment Study Of The Different Surgical Managements For The Open Fracture With Seawater Immersion

Objective :The purposes of this study is to explore which method, internal fixation or external fixation, is much efficacious in management of open fracture with seawater immersion by rabbit model.Methods: 50 New Zealand rabbits were divided into three groups randomly. There were 10 in control group, 20 in group A, 20 in group B. Osteotomy was conducted in the middle part of tibia. The animals of control group were exposed in the air for three hours and other animals of group A and B were fixed on the special shelf and immersed in seawater also for three hours. Wound debridement was given to each animal, then the animals of control group and group A were given internal fixation, contemporary, the animals of group B were applied by external fixation, the wound was kept opening, then, closed secondly. Ultimately, infection rate, histopathology, radiology and the grayscale at fracture site were observed.Results: 1.One wound was infected in the control group (10%); 15 wounds were infected in the group A (75%); 5 were infected in the group B (25%). There was a significant statistical difference between each two groups (p<0.05). 2. At 45 days postoperatively, pathological grading showed that there were grade II in 3, grade III in 5 of control group, respectively. There were grade I in 2, grade II in 2, grade III in 2 of group A, respectively. There were grade II in 7, grade III in 7 of group B. Statistic analysis showed a significant difference statistically between each two growp(p<0.05). 3. At 45 days postoperatively, the average grayscale at fracture site was 8.1149±1.2043, 6.2268±1.400 and 6.5138±1.3045 in control group, group A and group B, respectively. There was a significant difference statistically between each two groups(P<0.05). Conclusion: Wound infection rate was increased by seawater immersion. Bone healing was affected by seawater immersion. External fixation was better than the internal fixation in management the open fracture with seawater immersion. To the infected Wound, the management isn't effective in two stage.