Department of Orthopaedic Surgery, University of California Davis Medical Center, Sacramento, CA; and.
Department of Orthopaedic Surgery, University of Texas Health Sciences Center at Houston, Houston, TX.
J Orthop Trauma. 2021 Apr 1;35(4):175-180. doi: 10.1097/BOT.0000000000001942.
To determine whether fracture pattern, implant size, fixation direction, or the amount of posterior pelvic ring fixation influences superior ramus medullary screw fixation failure.
Retrospective cohort review.
Regional Level 1 trauma center.
PATIENTS/PARTICIPANTS: After exclusion criteria, 95 patients with 111 superior ramus fractures with 3 months minimum follow-up were included.
All patients underwent anterior and posterior pelvic ring fixation.
Comparison of immediate postoperative radiographs and/or computer tomography scan with the latest postoperative image to calculate interval fracture displacement and implant position. Postoperative fracture displacement or implant position change greater than 1 cm were considered fixation failures.
Five screws were defined as failures (4.5%), including 3 retrograde, 3 with bicortical fixation, 4 with a 4.5-mm screw, and 1 with a 7.0-mm screw. Fracture patterns included 2 oblique and 3 comminuted fractures. Based on the Nakatani classification, there were 3 zone II, 1 zone I, and 1 zone III. Failure modes included 3 with cut-out along the screw head and 1 cut-out and 1 cut-through at the screw tip.
Our incidence of superior pubic ramus intramedullary screw fixation failure was 4.5%. Even with anterior and posterior fixation along with precise technique, failures still occur without a common failure predictor. The percutaneous advantages and proven strength provided by an intramedullary implant make it desirable to help reestablish global pelvic ring stability. Biomechanical and clinical studies are needed to further understand intramedullary superior ramus screw fixation.
Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.
确定骨折类型、植入物大小、固定方向或后骨盆环固定的数量是否会影响耻骨上支髓内钉固定失败。
回顾性队列研究。
区域 1 级创伤中心。
患者/参与者：排除标准后，纳入 95 例耻骨上支骨折患者（111 处骨折），随访时间至少 3 个月。
所有患者均行前后骨盆环固定。
比较术后即刻的 X 线片和/或计算机断层扫描（CT）与最新的术后图像，以计算间隔骨折移位和植入物位置。术后骨折移位或植入物位置改变大于 1 cm 被认为是固定失败。
定义 5 根螺钉为失败（4.5%），包括 3 根逆行螺钉、3 根双皮质固定螺钉、4 根 4.5 mm 螺钉和 1 根 7.0 mm 螺钉。骨折类型包括 2 例斜形骨折和 3 例粉碎性骨折。根据 Nakatani 分类，有 3 例Ⅱ区、1 例Ⅰ区和 1 例Ⅲ区骨折。失败模式包括 3 例螺钉头切割穿出、1 例螺钉尖端切割穿出和 1 例螺钉尖端穿透。
我们耻骨上支髓内钉固定失败的发生率为 4.5%。即使采用前后固定和精确的技术，仍会出现无共同失败预测因素的失败。髓内植入物具有经皮优势和已证实的强度，有助于重新建立骨盆环整体稳定性，这是理想的。需要进行生物力学和临床研究，以进一步了解耻骨上支髓内螺钉固定。
治疗 IV 级。有关证据水平的完整描述，请参见作者说明。
