Objective: To compare the effectiveness of the femoral neck system (FNS) and inverted triangle cannulated screws (ITCS) for the treatment of Pauwels type Ⅲ femoral neck fractures.
Methods: The clinical data of 59 patients with Pauwels type Ⅲ femoral neck fractures treated between May 2019 and November 2020 were retrospectively analysed. The patients were divided into FNS group (28 cases) and ITCS group (31 cases) according to the different internal fixation. There was no significant difference in gender, age, affected side, body mass index, cause of injury, smoking history, alcohol abuse history, Pauwels angle, Garden classification, AO/Orthopaedic Trauma Association (AO/OTA) classification, and time from injury to operation between the two groups ( P>0.05). The operation time, incision length, intraoperative blood loss, extra assisted reduction procedures (Kirschner wire prying reduction or open reduction), hospitalization stay, and early complications were recorded and compared between the two groups. Garden index and Haidukewych score were used to evaluate fracture reduction. Fracture healing time, lateral thigh irritation, time of partial or total weight-bearing postoperatively, shortening length and degree of femoral neck, change of caput-collum-diaphysis (CCD) angle (the difference of CCD angle between immediate after operation and last follow-up), incidence of osteonecrosis of femoral head and revision surgery were recorded and compared between the two groups. Hip joint function were evaluated by Harris score.
Results: The operation time of FNS group was significantly shorter than ITCS group, and the incision length was significantly longer than ITCS group ( P<0.05). There was no significant difference in intraoperative blood loss, assisted reduction, Garden index, Haidukewych score, and hospitalization stay between the two groups ( P>0.05). All the incisions healed by first intention. There were 2 deep vein thrombosis in the FNS group and 1 pulmonary infection and 1 deep vein thrombosis in the ITCS group. No significant difference was found in the incidence of early postoperative complications (7.1% vs. 6.5%) between the two groups ( P=1.000). Patients in both groups were followed up 3-14 months, and there was no significant difference in follow-up time between the two groups ( t=-0.553, P=0.582). The fracture healing time, Harris score, and the partial weight-bearing time after operation of the FNS group were significantly better than those of the ITCS group ( P<0.05). However, there was no significant difference in total weight-bearing time between the two groups ( Z=-1.298, P=0.194). No lateral thigh irritation was found in the FNS group, while 10 patients in the ITCS group had lateral thigh irritation, and the incidence between the two groups (0 vs. 32.3%) was significant ( P=0.001). At last follow-up, the shortening length and degree of femoral neck and the change of CCD angle in FNS group were significantly less than those in ITCS group ( P<0.05). There was no patient with osteonecrosis of femoral head or reoperation in the FNS group, while 4 patients in the ITCS group underwent reoperation (including 2 cases of osteonecrosis of the femoral head). However, the incidences (0 vs. 6.5%; 0 vs.12.9%) between the two groups were not significant ( P=0.493; P=0.114).
Conclusion: Using FNS to treat Pauwels type Ⅲ femoral neck fracture is simple as well as able to reduce the shortening of the femoral neck and the change of the CCD angle. Also, FNS is conducive to the recovery of hip joint function, which should be considered as a new choice for the treatment of young femoral neck fracture patients.
目的: 比较股骨颈动力交叉钉系统（femoral neck system，FNS）和倒三角空心钉（inverted triangle cannulated screws，ITCS）治疗 Pauwels Ⅲ型股骨颈骨折的临床疗效。.
方法: 回顾分析 2019 年 5 月—2020 年 11 月收治的 59 例 Pauwels Ⅲ型股骨颈骨折患者临床资料，根据内固定方式不同分为 FNS 组（28 例）和 ITCS 组（31 例）。两组患者性别、年龄、侧别、身体质量指数、致伤原因、吸烟史、酗酒史、Pauwels 角、Garden 分型、国际内固定研究协会/美国骨创伤协会（AO/OTA）分型及受伤至手术时间等一般资料比较差异均无统计学意义（ P>0.05）。记录并比较两组患者手术时间、切口长度、术中出血量、辅助复位（经皮克氏针撬拨复位或切开复位）、住院时间和早期并发症，并采用 Garden 指数和 Haidukewych 评分评价骨折复位情况；术后定期随访，比较两组骨折愈合时间、有无大腿外侧激惹症状、术后部分或完全负重开始时间、股骨颈短缩长度和程度、颈干角变化（术后即刻与末次随访时颈干角的差值）、股骨头坏死及翻修手术等，采用 Harris 评分评价髋关节功能。.
结果: FNS 组手术时间短于 ITCS 组、切口长度大于 ITCS 组（ P<0.05）；两组术中出血量、辅助复位情况、Garden 指数、Haidukewych 评分及住院时间比较差异均无统计学意义（ P>0.05）。术后患者手术切口均Ⅰ期愈合；FNS 组术后早期发生下肢深静脉血栓形成 2 例，ITCS 组发生肺部感染 1 例、下肢深静脉血栓形成 1 例，两组术后早期并发症发生率（7.1% vs.6.5%）比较差异无统计学意义（ P=1.000）。两组患者均获随访，随访时间 3～14 个月，两组随访时间比较差异无统计学意义（ t=–0.553， P=0.582）。FNS 组骨折愈合时间快于 ITCS 组，髋关节 Harris 评分高于 ITCS 组，术后部分负重开始时间早于 ITCS 组，差异均有统计学意义（ P<0.05）；但两组完全负重开始时间差异无统计学意义（ Z=–1.298， P=0.194）。FNS 组患者均无大腿外侧激惹症状，ITCS 组有 10 例出现大腿外侧激惹症状，两组发生率（0 vs. 32.3%）比较差异有统计学意义（ P=0.001）。末次随访时，FNS 组股骨颈短缩长度及程度以及颈干角变化均小于 ITCS 组（ P<0.05）。FNS 组无股骨头坏死及翻修手术患者，ITCS 组 4 例患者行翻修手术（包括 2 例发生股骨头坏死患者），两组股骨头坏死发生率（0 vs.6.5%）及翻修手术率（0 vs. 12.9%）比较差异均无统计学意义（ P=0.493； P=0.114）。.
结论: FNS 治疗 Pauwels Ⅲ型股骨颈骨折操作简便，可减少股骨颈短缩和颈干角变化，有利于髋关节功能恢复，为青年股骨颈骨折治疗提供一种选择。.
Keywords: Femoral neck fracture; femoral neck system; internal fixation; inverted triangle cannulated screws; reduction.