【作者】 彭明；

【导师】 朱勇； 廖前德；

【作者基本信息】 中南大学 ， 外科学， 2007， 硕士

【摘要】 目的：设计“AO”C2型胫骨远端骨折实验模型，用于pilon骨折内固定力学性能测试；比较4种不同钢板力学性能，为临床选择提供力学依据；改良pilon骨折传统手术入路，使开放复位内固定成为微创经皮钢板内固定。方法：1、取新鲜健康成人尸体左侧小腿标本5具，于踝关节平面上方3cm处造成5mm骨质缺损，模拟胫骨干骺端粉碎骨折；远端骨折块矢状面纵行劈裂至胫骨远端关节面，模拟简单骨折；制成“AO”C2型胫骨远端骨折模型，以4种钢板依次固定，分别在中立，内翻，外翻，跖屈，背屈位置给予相同轴向压力载荷后测量胫骨远端内、外侧骨折块的位移变化。采用SPSS12.0统计软件比较各组钢板固定后的骨折块位移差异。2、传统Pilon骨折手术入路改良。结果：(一)力学测试1．内侧骨块位移：中位值比较：三叶草钢板和改良三叶草钢板固定组最小，其次为胫骨远端内侧解剖钢板组，胫骨远端外侧解剖钢板组最大。wilcoxon秩检验结果：在踝关节各种状态下改良三叶草钢板组与三叶草钢板组比较均无统计学差异(P＞0.05)；在踝关节内翻20°、30°、跖屈15°、背屈8°、16°状态下胫骨远端内侧解剖钢板组与三叶草钢板组比较有统计学差异(P＜0.05)，其余状态下比较无统计学差异(P＞0.05)；在踝关节各种状态下胫骨远端外侧解剖钢板组与三叶草钢板组比较均有统计学差异(P＜0.05)。2．外侧骨块的位移：中位值比较：三叶草钢板、改良钢板固定组和胫骨远端内侧解剖钢板组较小，胫骨远端外侧解剖钢板组较大。Wilcoxon秩检验结果：在踝关节各种状态下，改良三叶草钢板组与三叶草钢板组比较无统计学差异(P＞0.05)，胫骨远端内侧解剖钢板组与三叶草钢板组比较无统计学差异(P＞0.05)，胫骨远端外侧解剖钢板组与三叶草钢板组比较有统计学差异(P＜0.05)。3．内外侧骨块位移比较：外侧骨块位移较内侧骨块大，Wilcoxon秩检验两者比较有统计学差异(P＜0.01)。(二)手术入路改良内踝前或后弧形切口可清楚暴露踝关节，钢板插入简单、易行。结论：1．本研究首次设计出pilon骨折实验模型，基本符合临床实际情况，与AO分类完全吻合，可以运用于力学测试。2．pilon骨折运用钢板固定，其外侧骨折块存在塌陷危险，必要时应附加螺钉及植骨。3．胫骨远端骨折，如主要骨折线位于矢状面时，胫骨远端外侧解剖钢板不具备力学优势。4．用内踝前或后弧形切口可清楚暴露踝关节，钢板插入简单、易行更多还原

【Abstract】 Objective: To design experimental model of "AO" C2 type distal tibial fracture for biomechanical measurement of internal fixation in pilon fracture. Compare the biomechanical character of four kinds of internal fixation plate, so as to provide the mechanical basis for clinical application. Transform the open reduction and internal fixation into minimally invasive percutaneous osteosynthesis with the improvement of traditional approach.Methods:1. To get 5 left leg specimens from flesh-frozen health adult cadaver, make a 5mm deossification at the place of 3cm above ankle joint to simulate thrypsis of tibial metaphysis; split the distal bone block fore and aft to the distal articular surface of tibia, to simulate simple fracture. Manufacture the experimental model of"AO"C2 type distal tibial fracture. After fixed by four kinds of plate, the stress and displacement of the bone block were measured when the foot was at the same axial pressure and inthe position of neutrality、enstrophe、ecstrophy、plantar flexion and dorsiflexion, respectively. Analyze the stress and displacement with SPSS 12.0.2. Improve traditional approach of pilon fracture.Results:1. The biomechanical test:(1)The displacement of interior bone block: Median comparison:Which of the groups of clover plate and improved clover plate are minimum, the group of interior anatomy plate was the next, the group of lateral anatomy plate is maximum. Wilcoxon ranking test result:There are no significant difference between the group of clover plate and the group of improved clover plate under all of the conditions. (p＞0.05).The displacement in the group of interior anatomy plate has significant difference comparing with the group of clover plate when the ankle joint is on enstrophe 20°、30°、plantar flexion 15°、dorsiflexion 8°、16°(p＜0.05), and has no significant difference under the rest conditions. The displacement in the group of lateral anatomy plate has significant difference comparing with the group of dover plate under all of the conditions (p＜0.05).(2)The displacement of lateral bone block: Median comparison:Which of the groups of clover plate、improved clover plate and interior anatomyZ.(3)Displacement comparison between the interior bone block and the lateral bone block: The lateral bone block is greater than the interior bone block, there are significant difference between them(p＜0.001).2 Improvement of approach:The expose of the ankle joint is clear and the insertion of the plate issimple and easy with the application of the arcuated incision before or behind medial malleolus.Conclusions:1. It is the first time of the design of the experimental pilon fracture model, which is consistent with the clinical actuality and suitable for the biomechanical test.2. The lateral block of pilon fracture has a risk of collapse after fixed by the plate, so additional screw and bone graft is necessary.3. The lateral anatomy plate has no mechanical superiority when the main fracture line lies in vertical plane in distal fracture of tibia.4. The expose of the ankle joint is clear and the insertion of the plate is simple and easy with the application of the arcuated incision before or behind medial malleolus.更多还原