Femoral Neck Fracture With Anterior Tilt

Posteriorly tilted femoral neck fractures have been extensively studied, whereas anteriorly tilted fractures remain largely unreported. This study aims to characterize the clinical features, radiographic patterns, and postoperative outcomes of femoral neck fractures with anterior tilt.

This retrospective cohort study included adult patients with OTA/AO type 31B femoral neck fractures who underwent internal fixation within 36 h at a single orthopedic center from 2018 to 2022 and had ≥ 24 months of follow-up. Tilt angle was assessed using preoperative radiographs and CT. Associations between fracture characteristics and postoperative outcomes were examined using univariate and multivariable logistic regression, with covariates selected according to clinical relevance and univariate significance.

Among 212 patients (median age: 55 years, 53.3% male), anterior tilt fractures were more common in females (57.6%) and those with valgus malalignment (69.7%). Anteriorly tilted femoral neck fractures required a distinct reduction technique compared to conventional femoral neck fractures. Displaced fractures were significantly associated with a higher risk of femoral head necrosis (adjusted odds ratio [aOR] = 4.16; 95% confidence interval [CI] 1.29-13.42; p = 0.017). Stratified analysis revealed that anteriorly tilted femoral neck fractures with varus malalignment-herein referred to as the "anterior-flexion/adduction" subtype-were significantly associated with increased risk of femoral head necrosis (aOR = 7.19; 95% CI 1.12-46.18; p = 0.038).

Anterior tilt alone is not a general prognostic risk factor; however, fractures characterized by anterior tilt combined with varus alignment represent a high-risk subtype requiring careful preoperative recognition and treatment planning. Further prospective studies are needed to validate these findings.