单纯颧骨骨折理想内固定方式的生物力学研究

目的:探讨颧骨与邻骨连接断开移位,但颧骨本身无骨折的单纯颧骨骨折(Zingg分类B类)的理想内固定方式。方法:以12具头颅标本为研究对象,人为造成单纯颧骨骨折,然后采用1.3 mm微型钛板和2.0 mm小型钛板,分别进行4种不同方式(颧牙槽嵴一点式,颧牙槽嵴、颧额缝二点式,颧牙槽嵴、颧额缝、眶下三点式,颧牙槽嵴、颧额缝、颧颞缝三点式)的内固定,进行拉力试验检测4种内固定方式的最大抗拉力值,以判断其固定的可靠性。结果:除颧牙槽嵴一点式微板固定法的抗拉力值小于9.3 kg(最大咬肌牵引力)外,余固定方法抗拉力值均高于9.3 kg,均为可靠固定法。结论:对单纯颧骨骨折,颧牙槽嵴一点式2.0 mm小钛板固定法、颧牙槽嵴和颧额缝二点式1.3 mm微钛板固定法,能保证固定力且皮肤瘢痕最小,为获得可靠内固定的理想方法。

Biomechanics of Ideal Internal Fixation in Simple Displaced Fracture of Zygoma

Objective： To study the ideal internal fixation of simple displaced fracture of zygoma by biomechanics method. Methods： Malars of 12 cadaver heads were hammered with external force to produce the simple malar fracture, and fixed in four different ways with micro-titanium plates of 1.3 mm diameter or mini-plate of 2.0 mm diameter. The four fixation ways were： （1） one point fixation at zygaomaticomaxillary buttress （ZMB）, （2） two points fixation at zygomaticomaxillary buttress and zygomaticofrontal suture （ZMB ＋ZF）, （3）three points fixation at zygaomaticomaxillary buttress and zygomaticofrontal suture and inferior orbital rim （ZMB＋ZF＋IOR）, （4）three points fixation at zygomaticomaxilly buttress and zygomaticofrontal suture and zygomatico temporal suture （ZMB＋ZF＋ZT）. The critical force of 4 fixation ways were tested. Results： The critical force of micro-plate fixation at ZMB was less than 9.3 kg （the maximal masseteric muscle force）, and was thought to be instability. The results of other groups were all satisfied （〉9.3 kg）. Conclusion： One point mini-plate （2.0 mm） fixation at the ZMB, two point fixation microplate （1.3 mm） at the ZMB＋ZF are thought to be ideal way to simple malar fracture for reliable fixation with less scars.