Analysis of risk factors for changes in anteversion angle after intramedullary nail internal fixation of intertrochanteric femur fractures in the elderly
10.3760/cma.j.cn121113-20241028-00599
- VernacularTitle:老年股骨转子间骨折髓内钉固定术后前倾角变化的危险因素分析
- Author:
Chao HAN
1
;
Xiang SUN
1
;
Zhe HAN
1
;
Mengqi XIE
1
;
Weiwei HE
1
;
Qiang DONG
1
;
Xinlong MA
1
Author Information
1. 天津市天津医院(天津大学天津医院)髋关节科,天津 300211
- Publication Type:Journal Article
- Keywords:
Aged;
Femoral fractures;
Fracture fixation, intramedullary;
Risk factors
- From:
Chinese Journal of Orthopaedics
2025;45(8):478-484
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the degree of change in anteversion angle and related risk factors after intramedullary nail fixation of intertrochanteric femur fracture in the elderly.Methods:The data of 256 elderly patients who underwent intramedullary nail fixation for intertrochanteric fractures of the femur at Tianjin Hospital of Tianjin University from March 2020 to March 2023 were selected, including 114 males and 142 females, with an age of 75.40±10.69 years (range, 65-94 years). The degree of change in the anteversion angle of the affected hip before and after the surgery was measured by CT scan of the hip, the Receiver Operating Characteristic Curve (ROC) was plotted, the area under the ROC curve was analyzed, and the optimal degree of grouping was determined by calculating the Youden Index, then all the patients were divided into two groups. The correlation between various risk factors (age, sex, type of internal fixation, fracture AO type, quality of reduction, fracture medial cortical defect or not, cusp distance) and the change of anterior tilt angle was screened by univariate and multivariate logistic regression analyses.Results:All 256 patients were followed up for 20.7±2.1 months (range, 18-23 months). Anteversion on the healthy side was 12.68°±5.10° (range, 5°-28°); postoperative anteversion on the affected side was 15.04°±7.67° (range, 9°-36°). By comparing the difference in the anterior tilt angle between the affected side and the healthy side, it was found that the anterior tilt angle of 67 patients was completely restored to the healthy side level after the operation. The anteversion angle was enlarged in 131 cases, of which the mildly increased angle (1°-9°) was found in 106 cases, moderately increased (10°-15°) was found in 17 cases, and significantly increased (>15°) was found in 8 cases; 58 patients showed anteversion angle reduction, of which 45 cases were mildly reduced (1°-9°), 13 cases were moderately reduced (10°-14°). The area under the ROC curve for the patient's anteversion angle and its 95% CI were 0.714(0.559, 0.867), and the maximum value of its Youden Index was 0.221, which corresponded to the optimal critical angle of 4°. There was no statistically significant difference in age, gender, reduction quality or fracture AO classification between the group with an anteversion angle>4° and the group with an anteversion angle≤4° ( P>0.05). The types of internal fixation, medial cortical defect and insufficient tip apex distance (TAD) were included in the binary variable logistic regression analysis. The results showed that single-nail internal fixation [ OR=0.412, 95% CI(0.244, 0.695), P=0.007], medial cortical defect [ OR=0.471, 95% CI(0.279, 0.793), P=0.009] and TAD>25 mm [ OR=0.367, 95% CI(0.207, 0.651), P=0.003] are independent risk factors for changes in anteversion angle after intramedullary nail fixation of intertrochanteric femur fractures in elderly. Conclusion:Single-nail internal fixation, medial cortical defect and TAD >25 mm are independent risk factors for the change of anteversion angle after intramedullary nail internal fixation of intertrochanteric fractures in the elderly.