Department of Orthopedics, Fuzhou Second General Hospital, Fujian Provincial Clinical Medical Research Center for Trauma Orthopedics Emergency and Rehabilitation, Fuzhou, 350007, China.
Clinical Medical Department, Fujian Medical University, Fuzhou, 350007, China.
J Orthop Surg Res. 2024 Oct 26;19(1):690. doi: 10.1186/s13018-024-05190-0.
Displaced femoral neck fractures frequently result in considerable patient morbidity, with complications such as postoperative femoral neck shortening occurring in up to 39.1% of cases. This shortening is associated with reduced hip function and mobility. The Femoral Neck System (FNS), which allows for controlled sliding to facilitate fracture reduction and healing, may mitigate these issues. However, the ideal sliding distance to balance fracture healing and minimize complications is not well defined.
We performed a retrospective cohort study of 179 patients who underwent FNS fixation for displaced femoral neck fractures at our institution from September 2019 to September 2023. Patients were categorized into three groups based on the intraoperative sliding distance allowed by the FNS: the Minimal Slide group (≤ 5 mm), the Moderate Slide group (> 5 to ≤ 10 mm), and the Extensive Slide group (> 10 to 20 mm). Primary outcomes included postoperative femoral neck shortening, the incidence of moderate to severe shortening, time to fracture union, and hip joint function as assessed by the Harris Hip Score (HHS) and the Parker Mobility Score. Secondary outcomes included complication rates such as implant cut-out, nonunion, avascular necrosis of the femoral head, and the need for secondary surgery.
The Extensive Slide group of moderate to severe shortening at 32.31%, which was 1.59-fold and 8.88-fold that of the Moderate Slide (20.34%) and Minimal Slide group's (3.64%), respectively (P < 0.01). The sliding predominantly occurred within the first three months postoperatively and had substantially ceased by six months. At one year postoperatively, the median shortening was 2.7 mm (IQR, 0.7 to 3.5 mm) for the Minimal Slide group, a value that was notably lower compared to the 3.2 mm (IQR, 2.4 to 4.6 mm) for the Moderate Slide group and the 3.5 mm (IQR, 1.3 to 8.1 mm) for the Extensive Slide group. The average time to achieve union was similar across all groups, with no significant differences. Functional outcomes, as assessed by the Harris Hip Score (HHS) and the Parker Mobility Score, the Harris Hip Score (HHS) demonstrated statistical significance, the Parker Mobility Score did not reach statistical significance.
Restricting FNS slide to ≤ 5 mm in surgery may reduce shortening, improve hip function, and not hinder fracture healing or implant stability. Considering the key 3-month sliding timeline postoperatively is advisable in clinical practice. Further research with a broader patient cohort is vital to confirm these findings and to anchor them in evidence-based practice.
移位性股骨颈骨折常导致患者出现相当大的发病率，术后股骨颈缩短的并发症发生率高达 39.1%。这种缩短与髋关节功能和活动度降低有关。股骨颈系统（FNS）允许控制滑动，以促进骨折复位和愈合，可能减轻这些问题。然而，平衡骨折愈合和最小化并发症的理想滑动距离尚未明确界定。
我们对 2019 年 9 月至 2023 年 9 月在我院接受 FNS 固定治疗的 179 例移位性股骨颈骨折患者进行了回顾性队列研究。根据 FNS 术中允许的滑动距离，患者分为三组：最小滑动组（≤5mm）、中度滑动组（>5 至≤10mm）和广泛滑动组（>10 至 20mm）。主要结局包括术后股骨颈缩短、中重度缩短的发生率、骨折愈合时间以及髋关节功能（采用 Harris 髋关节评分（HHS）和 Parker 活动评分）。次要结局包括并发症发生率，如植入物穿出、不愈合、股骨头缺血性坏死以及需要二次手术。
广泛滑动组中中重度缩短的比例为 32.31%，分别是中度滑动组（20.34%）和最小滑动组（3.64%）的 1.59 倍和 8.88 倍（P<0.01）。滑动主要发生在术后三个月内，到六个月时已基本停止。术后一年时，最小滑动组的股骨颈缩短中位数为 2.7mm（IQR，0.7 至 3.5mm），显著低于中度滑动组的 3.2mm（IQR，2.4 至 4.6mm）和广泛滑动组的 3.5mm（IQR，1.3 至 8.1mm）。所有组的愈合时间平均相似，无显著差异。功能结局，如 Harris 髋关节评分（HHS）和 Parker 活动评分，Harris 髋关节评分（HHS）具有统计学意义，而 Parker 活动评分未达到统计学意义。
在手术中限制 FNS 滑动距离≤5mm 可能会减少缩短，改善髋关节功能，且不会妨碍骨折愈合或植入物稳定性。考虑到术后关键的 3 个月滑动时间线，这在临床实践中是明智的。需要进一步进行更大规模的患者队列研究，以证实这些发现并将其纳入循证实践。
