Department of Trauma Surgery, Faculty of Medicine P.J. Šafárik University and University Hospital of L. Pasteur, Rastislavova 43, 041 90 Košice, Slovak Republic.
Jt Dis Relat Surg. 2021;32(1):249-252. doi: 10.5606/ehc.2021.77186. Epub 2020 Sep 11.
The aim of this case report is to present an unusual mechanism of failure of a dynamic locking plate (DLP), previously reported in dual lag screw proximal femoral nails. A 78-year-old female patient experienced a displaced right femoral neck fracture (FNF) which was managed with DLP. At the postoperative sixth-week appointment, her hip radiographs showed that two of three telescoping screws had slid within the telescrew barrel, and one screw was fully extended and cutting through the femoral head. At the third-month checkup, radiographs revealed an unhealed FNF and 12 mm sliding on all three telescoping screws. At the final 11th-month follow-up, two screws were completely collapsed and the previously nonpenetrating screw was partially extended and cutting through the femoral head. Femoral neck shortening and femoral neck nonunion were noticed as well. In conclusion, the postoperative course of the case supports the hypothesis of a specific pattern of DLP failure resembling reversed Z- and Z-effects found in dual lag screw proximal femoral nails.
本病例报告旨在介绍一种动力锁定板（DLP）失效的罕见机制，此前在双拉力螺钉股骨近端髓内钉中已有报道。一位 78 岁女性患者发生移位性右侧股骨颈骨折（FNF），采用 DLP 进行治疗。术后第 6 周就诊时，其髋关节 X 线片显示三根伸缩螺钉中有两根已在伸缩螺钉管内滑动，一根螺钉完全伸出并穿过股骨头。在第三个月的检查中，X 线片显示 FNF 未愈合，三根伸缩螺钉均滑动了 12 毫米。在最终的第 11 个月随访时，两根螺钉完全塌陷，以前未穿透股骨头的螺钉部分伸出并穿过股骨头。还注意到股骨颈缩短和股骨颈不愈合。总之，本例的术后过程支持这样一种假设，即 DLP 失效的模式类似于双拉力螺钉股骨近端髓内钉中发现的反向 Z 型和 Z 型效应。
