*Department of Orthopedic Surgery, Seoul National University Boramae Hospital, Seoul, Korea; and †Department of Orthopedic Surgery, Seoul National University Hospital, Seoul, Korea.
J Orthop Trauma. 2013 Dec;27(12):696-701. doi: 10.1097/BOT.0b013e31829906a0.
To evaluate the incidence of femoral neck fracture (FNF) after removal of a compression hip screw (CHS) without trauma and to determine the risk factors for this type of fracture.
Retrospective study of consecutive patient series.
University teaching hospital.
Sixty-seven patients with a mean age of 65.3 years (45 women and 22 men).
A total of 67 implants were removed in the presence of bony consolidation of the fracture site; most of them were due to hardware pain.
The incidence of FNF after a CHS removal, clinical parameters (age, gender, bone mineral density, body mass index, and fracture stability), and radiologic parameters (the femoral neck-shaft angle, femoral neck width, distance between thread of lag screw, and neck cortex). Univariate analysis was performed for those parameters of the fracture group and the nonfracture group. To assess which variables were associated with FNF, a multiple logistic regression was used.
Six (9.0%) FNFs occurred within 1 month after a CHS removal. The mean anterior and lateral neck widths were significantly smaller, and the mean anterior and inferior thread-to-cortex distances were significantly shorter in the fracture group compared with the nonfracture group. The risk factor significantly associated with FNF was the inferior thread-to-cortex distance (odds ratio, 0.462; 95% confidence interval, 0.217-0.988).
CHS should not be removed routinely due to the risk of FNF. Furthermore, attention should be paid to at-risk patients with a hip screw positioned close to the inferior femoral neck cortex.
Prognostic level II.
评估无创伤情况下取出加压髋螺钉（CHS）后股骨颈骨折（FNF）的发生率，并确定这种类型骨折的危险因素。
连续患者系列的回顾性研究。
大学教学医院。
67 例患者，平均年龄 65.3 岁（45 名女性和 22 名男性）。
在骨折部位骨愈合的情况下共取出 67 个植入物；其中大多数是由于硬件疼痛。
CHS 取出后 FNF 的发生率、临床参数（年龄、性别、骨密度、体重指数和骨折稳定性）以及影像学参数（股骨颈干角、股骨颈宽度、拉力螺钉螺纹之间的距离和颈皮质）。对骨折组和非骨折组的这些参数进行单因素分析。为了评估哪些变量与 FNF 相关，使用了多元逻辑回归。
在 CHS 取出后 1 个月内发生了 6 例（9.0%）FNF。与非骨折组相比，骨折组的平均前颈和侧颈宽度明显较小，前下螺纹与皮质距离明显较短。与 FNF 显著相关的危险因素是下螺纹与皮质的距离（比值比，0.462；95%置信区间，0.217-0.988）。
由于存在发生 FNF 的风险，不应常规取出 CHS。此外，应注意螺钉位置接近股骨颈下皮质的高危患者。
预后 II 级。
