Orthopaedic surgery
Residual Positive Buttress Displacement After Femoral Neck System Fixation for Acute Femoral Neck Fractures: A Retrospective Cohort Study
By Xing J, Ren Y, Wang P and 1 others.
Abstract
Objective
When anatomical reduction cannot be safely achieved, the functional relevance of residual positive-buttress displacement after FNS fixation remains uncertain. Few clinical studies have quantified how its magnitude relates to hip function. To determine whether hip function after femoral neck system fixation differs by postoperative reduction pattern and, within positive-buttress reduction, by residual medial cortical displacement.
Methods
This retrospective cohort study included 180 adults with isolated acute femoral neck fractures treated with femoral neck system fixation between September 1, 2023, and April 30, 2024, and followed for at least 12 months. The overall analysis included Garden I-IV fractures; the exploratory five-group displacement analysis was restricted to Garden I-III fractures. Postoperative reduction was classified as anatomical reduction, positive-buttress reduction, or negative-buttress reduction. Positive-buttress displacement was measured on anteroposterior radiographs and categorized as PR-2 (≤ 2 mm), PR-4 (> 2-4 mm), or PR-6 (> 4 mm). The primary outcome was 12-month Harris Hip Score. Group comparisons used one-way analysis of variance, Kruskal-Wallis tests, chi-square or exact tests, and multivariable linear regression. Multivariable linear regression adjusted for age, sex, and Garden classification. Additional analyses evaluated continuous displacement, retained Garden IV fractures in the five-group comparison, and incorporated the available clinical covariates.