Risk factors for moderate and severe femoral neck shortening in displaced femoral neck fractures following treatment by a femoral neck system
10.3760/cma.j.cn115530-20230105-00008
- VernacularTitle:股骨颈动力交叉钉系统治疗移位型股骨颈骨折术后股骨颈中重度短缩的发生及危险因素分析
- Author:
Dongze LIN
1
;
Peisheng CHEN
;
Chaohui LIN
;
Bin CHEN
;
Ke ZHENG
;
Shunze ZHENG
;
Jiajie LIU
;
Fengfei LIN
Author Information
1. 福州市第二医院骨科，厦门大学附属福州第二医院，福建医科大学临床医学部，福建省创伤骨科急救与康复临床医学研究中心，福州 350007
- Keywords:
Femoral neck fracture;
Risk factors;
Fracture fixation, internal;
Femoral neck system
- From:
Chinese Journal of Orthopaedic Trauma
2023;25(11):952-958
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the incidence of and risk factors for femoral neck shortening in young and middle-aged patients with displaced femoral neck fracture treated by a femoral neck system (FNS).Methods:A retrospective study was conducted to analyze the clinical data of 135 patients with displaced femoral neck fracture who had been treated by closed reduction and FNS internal fixation at Department of Orthopaedics, The Second Hospital of Fuzhou from December 2019 to December 2021. There were 85 males and 50 females, with an age of 51 (42, 57) years and a body mass index of 22.6 (20.9, 24.2) kg/m 2. According to the Garden classification, there were 29 cases of type Ⅲ and 106 cases of type Ⅳ. Femoral neck shortening was observed. The patients' gender, age, side of shortening, body mass index, fracture type, high-energy injury, time from injury to surgery, cortical comminution at the fracture end, reduction quality (Garden index), partial weight bearing time, complete weight bearing time, and functional evaluation (Harris score) were recorded for a univariate analysis. Multivariate logistic regression was used to analyze the influencing factors for moderate to severe shortening. Results:All the 135 patients were followed up for 17.2 (15.0, 20.2) months. Different degrees of femoral neck shortening happened in all patients, yielding an incidence of 100%(135/135). The femoral neck shortening was 4.2 (2.6, 7.7) mm in displaced femoral neck fractures fixated by FNS. The shortening continued to worsen within the first 3 months after operation, reaching a stable state in the first 6 months. Persistent shortening hardly occurred after 6 months. According to the shortening distance, the patients were divided into a mild shortening group (76 cases <5 mm) and a moderate to severe shortening group (59 cases ≥ 5 mm). The Harris score at the last follow-up in the mild shortening group (91.7 ± 2.3) was significantly higher than that in the moderate to severe shortening group (87.9 ± 3.8) ( P<0.001). The fracture healing rate was 98.7% (75/76) in the mild shortening group and 98.3% (58/59) in the moderate to severe shortening group, showing no significant difference ( P=1.000). Logistic regression analysis found that the risk factors for moderate to severe shortening were fracture type (type Ⅳ) ( OR = 10.227, 95% CI: 1.845 to 56.693, P = 0.008), cortical comminution at the fracture end (if present) ( OR=52.697, 95% CI: 9.870 to 281.352, P<0.001), and partial weight bearing time <4 weeks ( OR = 0.168, 95% CI: 0.032 to 0.893, P = 0.036). Conclusions:The incidence of femoral neck shortening may be high in young and middle-aged patients with displaced femoral neck fracture treated by FNS, leading to decreased hip function. The main risk factors for femoral neck shortening are fracture type (Garden type Ⅳ), cortical comminution at the fracture end and partial weight-bearing time less than 4 weeks.
