ElMaraghy A W, ElMaraghy M W, Nousiainen M, Richards R R, Schemitsch E H
Musculoskeletal Research Laboratory, Division of Orthopaedic Surgery, Department of Surgery, St. Michael's Hospital and the University of Toronto, Toronto, Ontario, M5C 1R6 Canada.
J Orthop Trauma. 2001 Mar-Apr;15(3):186-91. doi: 10.1097/00005131-200103000-00007.
To determine the influence of the number of cortices of fixation on the stiffness of plate fixation of diaphyseal fractures.
Canine experimental study.
Tertiary referral and teaching hospital in Toronto, Canada.
Paired radii from fourteen skeletally mature, cross-bred dogs.
One member of each pair of radii was tested intact as a control, and the other had a transverse osteotomy plated sequentially with five to ten cortices of fixation on either side of the simulated fracture. Dynamic compression plates and limited contact dynamic compression plates were used in two groups with seven paired radii each. Normalized torsional stiffness and four-point bending stiffness were determined in the elastic range for the control and each of the plated constructs in both groups, using a materials testing machine.
The authors found no significant difference between the stiffness of the dynamic compression plates and limited contact dynamic compression plates. With either plate of a given length, significantly increased torsional stiffness is achieved with end bicortical screws. For bending stability with the plate at right angles to the bending plane, even short plated constructs have a stiffness exceeding that of intact bone.
For a transverse osteotomy with no fracture interdigitation, the bending rigidity with the plate at right angles to the bending plane is greater than the original stiffness of the bone for all constructs tested, with the exception of the limited contact dynamic compression plate with five cortices of fixation. The torsional rigidity of fixation only approaches the original rigidity of the bone for ten cortices of fixation with the dynamic compression plate and the limited contact dynamic compression plate.
确定固定皮质骨数量对骨干骨折钢板固定刚度的影响。
犬类实验研究。
加拿大多伦多的三级转诊和教学医院。
14只骨骼成熟的杂交犬的成对桡骨。
每对桡骨中的一根作为完整对照进行测试，另一根进行横向截骨，在模拟骨折两侧依次用5至10层皮质骨进行钢板固定。两组分别使用动力加压钢板和有限接触动力加压钢板，每组有7对桡骨。使用材料试验机在弹性范围内测定对照组以及两组中每个钢板固定结构的归一化扭转刚度和四点弯曲刚度。
作者发现动力加压钢板和有限接触动力加压钢板的刚度之间无显著差异。对于给定长度的任何一种钢板，使用双皮质骨端螺钉可显著提高扭转刚度。对于钢板与弯曲平面成直角的弯曲稳定性，即使是短的钢板固定结构，其刚度也超过完整骨骼的刚度。
对于无骨折嵌插的横向截骨，除了有5层皮质骨固定的有限接触动力加压钢板外，对于所有测试结构，钢板与弯曲平面成直角时的弯曲刚度大于骨骼的原始刚度。对于动力加压钢板和有限接触动力加压钢板，只有在有10层皮质骨固定时，固定的扭转刚度才接近骨骼的原始刚度。
