骨外固定治疗长骨缺损对肢体血液循环影响的实验研究

Changes of blood circulation of the extremity with tibia shaft defects treated with external fixation

目的 探讨短缩加压结合延长 (EECL)和骨节段延长转位 (SBTL)两种骨外固定基本方法在治疗长骨缺损中的合理选择。 方法 采用 10只山羊建立胫骨中段骨缺损模型 ,通过不同幅度的长骨缺损断端对位加压固定 ,观察骨缺损间隙软组织受压后对肢体远端血循环的影响。 结果 当骨缺损小于 15 %时 ,肢体远端血流未受明显影响 ;当骨缺损在 15 %～ 2 0 %时 ,缺损远端肢体血循环出现紊乱 ;当骨缺损超过 2 0 %时 ,可导致缺损处软组织挤压 ,血管扭曲闭塞 ,发生肢体远端血循环障碍。 结论 当缺损在 15 %范围以内时 ,应首选EECL方法 ;当缺损超过 2 0 %时 ,原则上应采用STBL方法 ;脉冲多谱勒可作为临床监测肢体血循环的参考指标。

Objective To study exyernal skeletal fixation for long tubular bony defect by end to end compression with lengthening (EECL) and segmental bone transport by lengthening (STBL). Methods About 20%-30% of the original length was resected from the middle shaft of the tibia in 10 goats of 1-2 years of age. The bony defect ends were shortened step by step with the sulcated half ring external fixator. Changes of the blood flow of the distant extremity were measured with pulse dopplar monitor, reference blood flow, and angiograph. Results The blood flow of the distant extremity was not affected when bony defect was less than 15% of the original length. Blood circulation disorder would appear in the distant extremity when bony defect ranged from 15% to 20% of the original length. The distant extremity would necrose because of obstruction of blood circulation when bony defect was more than 20% of the original length. Conclusions EECL can be recommended if bony defect is less than 15% of the original length. SBTL might be the only feasible way if bony defect is more than 20% of the original length. If bony defect is within 15% and 20%, EECL should be applied with great care while watching the extremity circulation with pulse Dopplar monitor.