Evans和Chrisman-Snook术式治疗踝关节外侧副韧带Ⅱ度损伤的生物力学比较

目的:测试Evans和Chrisman-Snook术式治疗踝关节外侧副韧带Ⅱ度损伤的术后稳定性,为临床治疗方法的选择及预后的判断提供依据。方法:2008年7月至2009年6月,采集18具冰冻下肢标本,男10例,女8例,平均年龄(39.3±11.2)岁,随机分为3组:正常对照组(A组),Evans术式组(B组)和Chrisman-Snook术式组(C组),每组6只标本。解冻后在B、C组中切断距腓前韧带和跟腓韧带,造成外侧副韧带Ⅱ度损伤,并采用Evans术式和Chrisman-Snook术式重建外侧副韧带,进行生物力学测试,观察胫距关节和距下关节侧方应力加载下的位移情况。结果:①胫距关节侧方应力试验显示B组对外侧副韧带损伤修复后位移大于A、C组(P<0.0001),A组与C组差异无统计学意义(P>0.05)。②距下关节侧方应力试验显示B组术后位移大于A、C组(P<0.0001),A组与C组差异无统计学意义(P>0.05)。结论:踝关节外侧副韧带损伤造成踝关节不稳,在其修复术式中Chrisman-Snook术式比Evans术式在重建踝关节术后初期稳定性上优于Evans术式,Chrisman-Snook术式更符合生物力学原理。

Biomechanical comparison of Evans procedure and Chrisman-Snook technique for the treatment of II degree lateral collateral ligament of ankle joint

Objective:To measure the stability of Evans procedure and Chrisman-Snook technique in the treatment of Ⅱ degree lateral collateral ligament of ankle joint,and provide basis for treatment and prognosis.Methods:From July 2008 to June 2009,18 frozen corpes were collected,including 10 males and 8 females,with an average age of fresh 39.3±11.2 years.The frozen corpes were randomly divided into three group,including normal controls(group A),Evans procedure(group B)and Chrisman-Snook technique(group C),6 specimens in each group.Anterior talofibular ligament and calcaneofibular ligament were cut off to causeⅡ degree lateral collateral ligament in group B and C.Evans procedure or Chrisman-Snook technique were applied to restore lateral collateral ligament,and measure biomechnics.The displacement of tibiotalar joint and subtalar joint were observed.Results:①The lateral stress results of tibiotalar joint showed the displacement by Evans procedure(group B) was greater than other groups(P<0.000 1).There were no significant differences between group A and C(P>0.05).②The lateral stress results of subtalar joint showed the displacement by Evans procedure(group B) was greater than other groups(P<0.000 1).There were no significant differences between group A and C(P>0.05).Conclusion:Ankle instability is caused by ankle joint lateral collateral ligament injury.Chrisman-Snook technique is better than Evans procedure in stability on the early stage of ankle joint restoration,and conform to principle of biomechanics.