Krettek C, Könemann B, Mannss J, Schandelmaier P, Schmidt U, Tscherne H
Unfallchirurgische Klinik, Medizinische Hochschule Hannover.
Unfallchirurg. 1996 Sep;99(9):671-8. doi: 10.1007/s001130050041.
While working to develop a distal locking device, we analyzed distal nail position with reference to nail deformation and a radiographic-morphometric investigation. The amount and the direction of implant deformation in unslotted stainless steel unreamed tibial nails (Synthes) were analyzed. Measurement of implant deformation (3 translations, 3 angles) in the center of the distal transverse locking hole was performed with a 3D magnetic motion tracker system before and after nail insertion. Unreamed tibial nails (diameter 8 mm, n = 10; diameter 9 mm, n = 10) were inserted in paired human cadaver tibiae. The results showed lateral translations of -4.5 +/- 3.5 mm (mean and standard deviation, range 14.3 mm) and dorsal translations of -7.8 +/- 5.8 mm (mean and standard deviation, range 19.2 mm). Rotational deformations around the longitudinal axis of the nail were 0.3 +/- 0.7 degree (mean and standard deviation, range 2.4 degrees). The results showed, that a simple aiming arm, mounted on the proximal nail end, alone or even in combination with a large working channel (e.g. 10 mm in diameter), was not adequate to the aiming process. A radiographic-morphometric analysis was subsequently performed in 40 tibiae after experimental (n = 20) or clinical (n = 20) implantation of nails 8 mm and 9 mm in diameter. These measurements showed a relatively constant distance between the upper distal transverse hole and the anterior aspect of the tibia (average 12.3 mm and only a narrow range (7.6 mm). These data were the basis for the development of an aiming technique that exploits the relatively constant distance between the distal nail hole and the anterior aspect of the tibia. This aiming device is set at a distance of 12.3 mm from the anterior cortex, and the fine tuning is finally resolved by the use of a "working channel' 10 mm in diameter.
在致力于研发一种远端锁定装置时，我们通过参考钉的变形情况及影像学形态测量研究，对远端髓内钉位置进行了分析。分析了非开槽不锈钢非扩髓胫骨髓内钉（辛迪斯公司生产）的植入物变形量及方向。在髓内钉插入前后，使用三维磁运动跟踪系统对远端横向锁定孔中心处的植入物变形（3个平移量、3个角度）进行测量。将非扩髓胫骨髓内钉（直径8毫米，n = 10；直径9毫米，n = 10）插入成对的人体尸体胫骨中。结果显示，横向平移为-4.5±3.5毫米（平均值及标准差，范围为14.3毫米），背侧平移为-7.8±5.8毫米（平均值及标准差，范围为19.2毫米）。围绕髓内钉纵轴的旋转变形为0.3±0.7度（平均值及标准差，范围为2.4度）。结果表明，仅安装在近端髓内钉末端的简单瞄准臂，单独使用或甚至与大的工作通道（如直径10毫米）结合使用，都不足以完成瞄准过程。随后，在40例胫骨中进行了影像学形态测量分析，这些胫骨分别接受了实验性（n = 20）或临床性（n = 20）植入直径8毫米和9毫米的髓内钉。这些测量结果显示，远端上横向孔与胫骨前方之间的距离相对恒定（平均12.3毫米，范围仅为7.6毫米）。这些数据是研发一种利用远端髓内钉孔与胫骨前方相对恒定距离的瞄准技术的基础。该瞄准装置设置在距前皮质12.3毫米的距离处，最终通过使用直径10毫米的“工作通道”进行微调来解决瞄准问题。
