Similar radiological outcomes between inferior-center and center-center lag screw positions in femoral intertrochanteric fracture surgeries

Youh-Hua Lo ； Yu-Cheng Yeh ； Chang-Heng Liu ； Ying-Chao Chou ； Yung-Heng Hsu ； Yi-Hsun Yu

《Formosan Journal of Musculoskeletal Disorders》 13卷2期 (2022/05) Pp. 59-68

https://doi.org/10.6492/FJMD.202205_13(2).0001

摘要

Background: The center-center (CC) lag screw position has been widely accepted as the optimal lag screw position in femoral intertrochanteric fracture (FITF) surgery to achieve a tip-apex distance (TAD) of ＜ 25 mm. Despite some biomechanical advantages regarding the inferior-center (IC) lag screw position and the emergence of the calcar-referenced tip-apex distance (CalTAD), the clinical differences between the two commonly placed lag screw positions remain unclear. Purpose: This study aimed to report radiological outcomes in managing geriatric FITFs and identify the influences of the lag screw position. Methods: We retrospectively assessed the clinical and radiographic findings of geriatric patients (age ≥ 60 years) who underwent osteosynthesis for acute closed FITFs using either dynamic hip screw (DHS) or Gamma 3 nail (Gamma) fixation during a 1-year period and were followed up for a minimum of 12 months. The radiographic parameters and incidence of fixation failure were compared between different lag screw positions (CC vs. IC). Subgroup analyses of different implant types (DHS and gamma) were also performed to compare different lag screw positions. Results: A total of 112 patients (4.5%) with fixation failure were included. There were no differences in the incidence of fixation failure between the commonly inserted 2 lag screw positions, regardless of the implant type. The lag position other than the CC or IC position revealed a higher rate of poor reduction quality, lesser neck-shaft angle, and a higher rate of fixation failure. Regarding each implant, comparable results were obtained for either the lag screw positioned in the CC or IC. Conclusion: Regardless of implant type, the surgical results were comparable between the CC and IC positions of the lag screw as long as the rules of TAD and CalTAD were followed.

關鍵字

calcar referenced tip-apex distance ； geriatric fractures ； intertrochanteric fracture ； tip-apex distance