胫骨骨折单臂外固定架固定术后足拇下垂的临床研究

The Clinical Study of Dropped Hallux after Fixation of Tibial Fractures with the Unilateral External Fixator

目的研究胫骨骨折单臂外固定架固定术后出现足拇下垂的发生率、危险因素、原因及预防。方法对239例胫骨骨折单臂外固定架固定的患者进行回顾性研究。结果11例(4.6%)术后发生足拇下垂及第一趾蹼区麻木,足拇背屈肌力均为0级,其中8例术后24h内出现,经肌电图检查证实腓深神经传导速度减慢。年龄平均26.8岁,胫骨中上1/3骨折9例,间接暴力骨折8例,A型骨折(AO分型)9例,10例为闭合骨折并行闭合复位单臂外固定架固定术,平均复位2次。3例因术后前筋膜室压力大于30mmHg,再次手术行切开减压术,术后4周3例中1例足拇背伸肌力仍为0级。3～6个月10例肌力恢复为5级,1例为4级。结论本研究报告了足拇下垂的发生率及一些危险因素,并探求其原因,推荐使用小切口切开复位外固定架固定术。

Objective To study the incidence, the risk factors and the causes as well as the prevention of the dropped hallux after the fixation of tibial fractures with the unilateral external fixator. Methods A retrospective study on 239 patients with tibial fractures treatedwith the unilateral external fixator was performed. Results Eleven （4.6%） patients developed the dropped hallux syndrome with Grade 0 muscle strength of extensor hallucis longus and numbness in the first web space. It was proved that the conduction velocity of the deep peroneal nerve decreased in the elcctromyogram in 8 patients 24 hours postoperatively. The average age was 26.8 years old. The fracture in the medial superior one- third of tibia occurred in 9 patients. The fracture in 8 patients was caused by the indirect force, 9 cases were type A fracture. Ten cases were the close fracture and treated with close reduction and the unilateral external fixator with average t,wicc reduction. Because of the pressure in the anterior compartment was more than 30 mm Hg in 3 patients, open decompression was performed. Four weeks after the operation the muscle strength of extensor hallucis longus in 1 of the 3 patients was still grade 0, and grade 5 in 10 patients and grade 4 in one patient 3 to 6 months postoperatively. Conclusion The incidence and some risk factors are identified and the technique of open reduction fixation with the small incision is proposed in this study.