Vertical projection spacing of the center of rotation-posterior inner edge of the greater trochanter combined with the mirror technique to correct the rotation deformity of femoral shaft fracture
10.3760/cma.j.cn121113-20231108-00296
- VernacularTitle:旋转中心-大转子后内缘垂直投影间距结合"镜像"技术在矫正股骨干骨折旋转移位中的应用
- Author:
Chengzhi YANG
1
;
Gang LIU
;
Jianming HE
;
Jingli TANG
;
Gaorong LI
;
Xiangtao XIE
;
Juzheng HU
Author Information
1. 广西医科大学第四附属医院（柳州市工人医院）创伤中心，柳州 545005
- Keywords:
Femoral fractures;
Fractures, comminuted;
Fracture dislocation;
Rotation;
Fracture fixation, intramedullary
- From:
Chinese Journal of Orthopaedics
2024;44(15):1010-1017
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the feasibility and clinical efficacy of using the mirror technique, which involves overlapping the distance between the center of rotation of the femoral head and the posteromedial edge of the greater trochanter, combined with the injured side and the posterior edge of the contralateral femoral medial and lateral condyles, to correct rotational displacement of the femur during closed reduction and intramedullary nail fixation for multi-level comminuted femoral shaft fractures.Methods:This study included 52 adult patients with unilateral comminuted femoral shaft fractures treated with closed reduction and antegrade interlocking intramedullary nail fixation at the Trauma Center of Liuzhou Workers' Hospital from January 2020 to December 2022. The cohort consisted of 37 males and 15 females, with an average age of 44.4±3.5 years (range 19-68 years). During the operation, C-arm fluoroscopy was used to confirm the standard lateral position of the knee joint, identified by overlapping the posterior edges of the medial and lateral femoral condyles. With this position maintained, X-ray fluoroscopy was performed on the hip joint in the anteroposterior view to identify the rotation center of the femoral head (point O) and the intersection point of the arc projection between the posteromedial edge of the greater trochanter and the upper edge of the femoral neck (point Y). The distance from point O to point Y (OY) was measured and recorded. The rotational deformity of the femoral shaft fracture was corrected by internally or externally rotating the main screw sight frame to match the OY distance between the injured and healthy sides. Postoperative CT was used to measure bilateral femoral neck anteversion (FNA), and the difference in FNA between the two sides was compared to verify the accuracy of rotation control. Clinical efficacy was evaluated based on fracture healing rate, lower extremity functional scale (LEFS) score, Harris score, Lysholm knee score, hip and knee joint range of motion, and complications.Results:The postoperative FNA was 14.45°±3.23° on the healthy side and 14.21°±3.28° on the injured side. The mean FNA difference between the two sides was 0.79°±0.58° (range 0°-2.5°). In 3 cases, the difference exceeded 2°, with a maximum difference of 2.5°. In 10 cases, the difference ranged from 1° to 2°, and in 39 cases, the difference was ≤1°, including 2 cases with no difference. There was no significant difference in postoperative FNA between the two sides ( t=1.063, P=0.168). At the last follow-up, there were no significant differences in LEFS score, Harris score, or Lysholm score between the injured and healthy sides ( P>0.05). The range of motion (ROM) of the hip joint at the last follow-up was 117.0°±2.2° in flexion, 24.3°±3.2° in extension, 33.4°±3.1° in abduction, 20.8°±2.7° in adduction, 19.4°±3.5° in internal rotation, and 38.2°±1.5° in external rotation. The ROM of the healthy side was 122.0°±2.4° in flexion, 25.4°±2.8° in extension, 35.6°±2.0° in abduction, 23.4°±1.6° in adduction, 21.0°±2.2° in internal rotation, and 38.4°±1.8° in external rotation, with no significant differences ( P>0.05). The knee flexion ROM was 135.0°±2.8° on the injured side and 138.4°±1.2° on the healthy side, with no significant difference ( P>0.05). The fracture healing time was 10.6±2.3 months (range 6-13 months). One patient developed fat embolism syndrome on the third postoperative day and recovered after 2 weeks of hormone therapy and respiratory support. No other complications, such as vascular or nerve injury, infection, deep vein thrombosis, or joint dysfunction, were observed in the remaining 51 patients. Conclusion:The method of using the vertical projection distance between the center of rotation of the femoral head and the posteromedial edge of the greater trochanter, combined with the overlap of the injured side and the posterior edge of the medial and lateral femoral condyles, is a new quantitative approach. This technique accurately determines and corrects the rotational displacement of femoral fractures, offering an effective and quick intraoperative correction method.
