Burkhart Klaus J, Nowak Tobias E, Gradl Georg, Klitscher Daniela, Mehling Isabella, Mehler Dorothea, Mueller Lars P, Rommens Pol M
Department of Trauma Surgery, Center for Musculoskeletal Surgery, University Medical Center of the Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany.
Clin Biomech (Bristol). 2010 Oct;25(8):771-5. doi: 10.1016/j.clinbiomech.2010.06.004. Epub 2010 Jul 7.
The purpose of this study was to compare the stability of a 2.4mm palmar locking compression plate and a new intramedullary nail-plate-hybrid Targon DR for dorsally comminuted distal radius fractures.
An extraarticular 10mm dorsally open wedge osteotomy was created in 8 pairs of fresh frozen human radii to simulate an AO-A3-fracture. The fractures were stabilized using one of the fixation methods. The specimens were loaded axially with 200 N and dorsal-excentrically with 80 N. 2000cycles of dynamic loading and axial loading-to-failure were performed.
Axial loading revealed that intramedullary osteosynthesis (Targon DR: 369 N/mm) was significantly (p=0.017) stiffer than plate osteosynthesis (Locking compression plate: 131 N/mm). With 214 N/mm the intramedullary nail also showed higher stability during dorsal excentric loading than the Locking compression plate with 51 N/mm (p=0.012). After 2000 cycles of axial loading with 80 N the Targon DR-group was significantly stiffer than the Locking compression plate-group under both loading patterns. Neither group showed significant changes in stiffness after 2000 cycles. Under dorsal excentric loading the Targon DR-group was still significantly stiffer with 212 N/mm than the Locking compression plate-group with 45 N/mm (p=0.012). The load to failure tests demonstrated higher stability of intramedullary nailing (625 N) when compared to plate osteosynthesis (403 N) (p<0.025).
The study shows that intramedullary fixation of a distal AO-A3 radial fracture is biomechanically more stable than volar fixed-angle plating under axial and dorsal-excentric loading in an experimental setup.
本研究旨在比较2.4mm掌侧锁定加压钢板与新型髓内钉-钢板混合式Targon DR治疗桡骨远端背侧粉碎性骨折的稳定性。
在8对新鲜冷冻的人体桡骨上制造一个10mm背侧开放性楔形关节外截骨，以模拟AO-A3型骨折。采用其中一种固定方法使骨折稳定。标本轴向加载200N，背侧偏心加载80N。进行2000次动态加载和轴向加载至破坏试验。
轴向加载显示，髓内固定（Targon DR：369N/mm）比钢板固定（锁定加压钢板：131N/mm）显著更硬（p = 0.017）。在背侧偏心加载时，髓内钉的稳定性也高于锁定加压钢板，分别为214N/mm和51N/mm（p = 0.012）。在80N轴向加载2000次循环后，Targon DR组在两种加载模式下均比锁定加压钢板组显著更硬。两组在2000次循环后刚度均无显著变化。在背侧偏心加载下，Targon DR组仍显著更硬，为212N/mm，而锁定加压钢板组为45N/mm（p = 0.012）。破坏载荷试验表明，与钢板固定（403N）相比，髓内钉固定（625N）具有更高的稳定性（p<0.025）。
该研究表明，在实验设置中，AO-A3型桡骨远端骨折的髓内固定在轴向和背侧偏心加载下比掌侧角钢板固定在生物力学上更稳定。
