摘要目的 分析踝关节骨折伴下胫腓联合分离的X线与CT影像学表现,为诊断下胫腓联合损伤提供更为准确的参照标准.方法 对2009年1月至2011年12月收治的36例踝关节骨折伴下胫腓联合损伤患者进行回顾性分析,男16例,女20例;年龄18～67岁,平均41.9岁.术前均行X线及CT检查.测量X线片和CT上的下胫腓胫距关节上10 mm处间隙距离,并进行比较. 结果 踝关节骨折伴下胫腓联合分离在X线片上中胫距关节上10 mm处清晰间隙为(7.95±0.49) mm,CT平扫测量胫距关节上10 mm处的胫腓骨间距为(8.48±0.41) mm,差异有统计学意义(t=-3.376,P=0.002).以下胫腓间隙大于6mm为标准的影像学诊断,有6例X线踝穴位小于6 mm,而CT测量下胫腓骨间隙小于6 mm的有2例,X线的漏诊率(16.7％)高于CT(5.6％),差异有统计学意义(x2=2.250,P=0.034). 结论 标准的X线成像及CT平扫均能诊断踝关节骨折伴下胫腓联合分离,但CT能够减少X线由于人为因素的干扰对下胫腓联合分离致踝关节不稳的漏诊,更有利于显示下胫腓联合分离的情况.

abstractsObjective To compare the X-ray and CT manifestations of ruptured distal tibiofibular syndesmosis coupled with ankle fracture for better diagnosis of lower tibiofibular syndesmosis injury.Methods A retrospective study was performed of 36 patients who had been treated in our department for ankle fracture complicated with distal tibiofibular syndesmosis injury from January 2009 to December 2011.They were 16 men and 20 women,18 to 67 years of age (average,41.9 years).They all had anterior-posterior X-ray and CT examinations preoperatively.The clear gaps and lower tibiofibular distances 10 mm above the tibial astragaloid joint were measured respectively on X-ray films and CT scans.The differences were compared between positive X-ray clear gaps and CT lower tibiofibular distances.Results The mean X-ray clear gap 10 mm above the tibial astragaloid joint was 7.95 ± 0.49 mm while the mean CT lower tibiofibular distance 10 mm above the tibial astragaloid joint was 8.48 ± 0.41 mm.The difference was significant (t =-3.376,P =0.002).The ankle mortise was less than 6 mm in 6 X-ray films,giving a rate of missed diagnosis of 16.7％ while the lower tibiofibular distance was hess than 6 mm in 2 CT scans,giving a rate of missed diagnosis of 5.67％.The difference was significant (x2 =2.250,P =0.034).Conclusions Both standard X-ray imaging and CT scan can detect ankle fracture complicated with separation of distal tibiofibular syndesmosis,but CT may lead to a reduced rate of missed diagnosis compared with X-ray,displaying the situation of distal tibiofibular syndesmosis injury more precisely and clearly.