FEMORAL NECK FRACTURE TREATED WITH CANNULATED SCREWS: IS REDUCTION THE KEY POINT?

Abstract

Background: In middle-aged patients, treatment of femoral neck fractures is still debated between osteosynthesis and replacement. Describing predictive factors is essential to choose the appropriate treatment for each patient. The aim of this study was to describe risk factors for avascular necrosis (AVN) of the femur head in patients with femoral neck fractures treated with three cannulated screws. Methods: We conducted a retrospective study of 91 patients between January of 2011 and February of 2017. Fractures were classified according to Garden and Pauwels classifications, fracture displacement was measured in millimetres (mm), quality of reduction was classified as anatomical or not anatomical; all post-operative radiographs were classified with Garden Alignment Index (GAI). Demographic data were recorded and analyzed. Results: AVN was found in six cases (6.6%). The Garden Classification ([Formula: see text]), GAI classification ([Formula: see text]), fracture displacement in mm ([Formula: see text]) and anatomical reduction ([Formula: see text]) were significantly associated with AVN. The most important risk factor for AVN was suboptimal reduction in axial view evaluated with GAI ([Formula: see text]). One case of AVN occurred in patients with GAI considered excellent (71.42%); no AVN occurred in patients with anatomical reduction (47.2%). Conclusions: Anatomical reduction in patients with femoral neck fractures treated with cannulated screws is mandatory. The degree of displacement before surgery influences the outcome but post-operative anatomical reduction, especially in the lateral view, is the most important predictive factor for the outcome: decreasing the Lateral Garden Angle (LGA) from 180∘increases significantly the risk for AVN.