Outcomes of Intramedullary Hip Screw Fixation for Intertrochanteric Proximal Femur Fracture: A Comparison between the Patients with and without Wedge Effect

Abstract Background: Intertrochanteric fractures (ITFs) are very common injuries seen in following ground-level falls in the elderly. In the most recent decade, the use of intramedullary (IM) devices to treat ITFs has gained popularity. O’Malley et al . first described the lateralization of the femoral shaft and the femoral neck varus malalignment occur following IM nail fixation for ITF. Objectives: The objective of this study was to the best of our knowledge, no study has investigated the association between the wedge effect in patients with ITF and postoperative functional outcomes in a large cohort with a minimum 1-year follow-up. This study aims to evaluate the function outcomes and radiological outcomes of the wedge effect in patients with ITFs. Materials and Methods: Three hundred and seventy-seven patients with ITFs fixed with proximal femoral nail were assessed. The medialized greater trochanter and the “crossing wire sign” were used as predictors of iatrogenic varus displacement. Function and clinical outcomes were measured by the Harris hip score (HHS), Visual analog scale (VAS), and nonunion rate. Radiological outcome was measured by tip apex distance (TAD), any changes in neck shaft angle, and cutout of the cephalic component. Results: The mean VAS was 1.82 for Group A and 1.57 for Group B. The mean HHS of the wedge effect group was 81.5, and no wedge effect group was 84.3. Furthermore, the mean TAD in patients with wedge effect was higher in those without wedge effect (27.4 mm vs. 23.3 mm, P = 0.069). The blade cutout rate was significantly higher in patients with wedge effect than in those without wedge effect (18% vs. 5%, P = 0.037). Conclusions: This study showed that the wedge effect increases the risk of blade cutout. We did not observe a significant association between the wedge effect and union rate.