踝关节跖屈、背屈运动的研究

目的:研究Pilon骨折在治疗中评价踝关节功能,诊断下胫腓联合分离、踝关节前后脱位的影像学依据。方法:35例正常成人,男21例(42踝),女14例(28踝);年龄21-48岁,平均31.6岁。踝关节常规摄正、侧位X线片;测量踝关节主动跖屈、背屈运动的最大角度,下胫腓联合间隙的宽度,胫骨外侧与腓骨的胫侧重叠影宽度,距骨踝关节面几何中心偏离胫骨中轴线的距离。结果:跖屈主动运动的最大角度,男(40.8°±3.1°),女(43.9°±4.8°);背屈主动运动的最大角度,男(27.6°±5.2°),女(26.5°±6.1°)。下胫腓联合间隙的宽度平均(3.2±0.5)mm。胫骨外侧与腓骨的胫侧重叠影宽度平均(6.9±2.2)mm。踝关节的跖屈下胫腓联合有逐渐变窄的变化,平均2 mm。距骨中心中轴距:男性跖屈最大值2.4 mm、背屈2.5 mm,女性跖屈最大值1.9 mm、背屈2.0 mm,最小值均为0 mm。结论:男女之间无论是背屈还是跖屈均无显著性差异(P>0.05),即踝关节在运动灵活性上无性别差异。踝关节主动跖屈、背屈运动的最大角度为Pilon骨折术中踝关节功能评定提供参考,下胫腓联合宽度>3.5 mm为下胫腓联合分离,胫骨外侧与腓骨的胫侧重叠影宽度<5.5 mm时,有下胫腓联合分离的可能。距骨中心中轴距>2 mm提示踝关节前后脱位。Pilon骨折在恢复骨折解剖复位的同时要注意这两个指标,对于恢复踝关节的侧方稳定、前后方向稳定有重要意义,能指导踝关节骨折治疗和康复。

Research of movement of plantarflexion and dorsiflexion of the ankle

Objective:To provide medical image evidence to the function evaluation of ankle,the diagnosis of the lower tibiofibular symphysis separation and ankle front-back dislocation in the treatment of Pilon fracture.Methods:The frontal and lateral X-ray image of ankle in 35 adults were obtained including 21 males(42 ankle),14 females(28 ankle) age from 21 to 48 years(mean 31.6 years).The maximal angle of initiative movement of plantarflexion and dorsiflexion of ankle and the width of peripheral tibiofibular joint,the width of the overlap image of lateral tibia and fibula,and the distance between geometrical center of the articular surface of talus-ankle and middle axes of shank were measured.Results: No statistical significance was found in ankle dorsiflexion(male 27.6°±5.2°;female 26.5° ±6.1°) and plantarflexion(male 40.8°±3.1°;female 43.9°±4.8°) between male and female.Width of peripheral tibiofibular joint beyond 3.5 mm and the overlap of distal tibia and fibula less than 5.5 mm were indicated joint separation.The width of peripheral tibiofibular joint varied little in ankle neutral and dorsiflexion position but lessened by 2 mm were indicated anterior-posterior ankle dislocation.The distance of geometrical center:maximum of ankle dorsiflexion was 2.4 mm and plantarflexion was 2.5 mm in male,ankle dorsiflexion maximum was 1.9 mm and plantarflexion 2.0 mm in female;The minimum of them was all 0 mm.Conclusion:No obvious difference exist(P>0.05) between male and female,either in dorsiflexion or in plantarflexion,there is no gender difference in the flexibility of the ankle movement.The maximal angle of initiative movement of plantarflexion and dorsiflexion of ankle offers a reference to the assessment to the function of ankle in the Pilon fracture.When the width of lower tibiofibular symphysis is more than 3.5 mm,it is considered as lower tibiofibular symphysis separation.When the width of the overlap image of lateral tibia and fibula is less than 5.5 mm,there is possibility that lower tibiofibular symphysis separation would happen,the distance which is more than 2 mm between geometrical center of the joint surface of talus-ankle and middle axes of shank gives a clue to front-back dislocation of anklebone.It is of big significance for the lateral stability and front-back stability of the ankle recovery to notice the two indexes at the same time within the anatomy location recovery of Pilon fracture,and it can as well instruct the treatment and recovery of anklebone fracture.