下胫腓联合损伤的术中分型和内固定选择

A new intraoperative classification of distal tibiofibular syndesmosis injury and internal fixation

目的探讨踝关节骨折中下胫腓联合损伤的术中分型对内固定选择的指导作用。方法对2010年1月至2015年1月收治且获得随访的116例WeberB、C型踝关节骨折患者资料进行回顾性分析，男60例，女56例；年龄18～78岁，平均45．6岁；术中在腓骨骨折复位固定后，通过腓骨牵拉试验结合影像检查结果判断下胫腓联合的损伤程度和稳定性，并将下胫腓联合损伤分为3型：下胫腓联合部位间隙〈4mm诊断为I型，下胫腓联合部位间隙4—7mm诊断为Ⅱ型，下胫腓联合部位间隙〉7mm诊断为Ⅲ型。根据分型结果选择适当的螺钉固定方式。采用美国足踝外科协会（AOFAS）的踝一后足评分评定疗效。结果本组116例患者中合并下胫腓联合损伤82例（70．7％），其中稳定的I型患者30例（25．9％）未进行下胫腓联合螺钉固定。下胫腓联合损伤后不稳定者（Ⅱ、Ⅲ型）52例（44．8％）：48例Ⅱ型患者中有4例经Volkmann骨折块固定后变为稳定型，未给予下胫腓联合螺钉固定，其余44例给予1枚螺钉固定；4例Ⅲ型患者给予2枚螺钉固定。本组患者术后获时间12—60个月随访，无发生骨折不愈合、下胫腓联合固定螺钉断裂发生，无螺钉取出后下胫腓联合分离复发病例，AOFAS的踝．后足评分优良率为93．1％（108／116）。结论新型的下胫腓联合稳定性术中分型能正确判断下胫腓联合的损伤程度，指导选择适当固定螺钉，提高了踝关节手术治疗的效果。

Objective To investigate the guidance of a new intraoperative classification of distal tibiofibular syndesmosis injury in the selection of internal fixation for ankle fractures. Methods Between January 2010 and January 2015 our department treated 116 patients with displaced closed ankle fracture （Weber type B or C）. They were 60 men and 56 women, aged from 18 to 78 years （average, 45.6 years）. After reduction and fixation of the fibular fracture, we assessed the syndesmosis stability using the fibular hook traction test and radiological findings. We classified the distal tibiofibular syndesmosis injury into 3 grades （grade I： 〈 4 mm displacement; grade II： 4-7 mm displacement; grade III： 〉 7 mm displacement） . Se- lection of proper screwing was determined by our new classification. Results Of the 116 cases, 82 （70. 7% ） demonstrated distal tibioflbular syndesmosis injury. Screwing of the distal tibiofibular syndesmosis was not conducted for 30 （25.9%） of them who were of stable grade L 52 （44.8%） cases were of unstable grades 11 and 11I. Of the 48 cases of grade 11, 44 were fixated with one screw and the rest 4 became stable grade I after Volkmann block fixation and received no screwing. Fixation of the distal tibiofibular syndesmosis with 2 screws was conducted for the 4 cases of unstable grade III. All the patients were followed up for 12 to 60 months. No non-union, screw breakage, or syndesmosis separation after screw removal occurred. The American Orthopaedic Foot and Ankle Society ankle-hindfoot scoring showed a good/excellent rate of 93.1% （108/116） . Conclusion Our new intraoperative classification can provide correct judgment of the severity of distal tibiofibular syndesmosis injury, thus guiding the selection of proper screw fixation to enhance the outcomes of ankle fractures.