Addressing posterior tilt displacement during surgery to lower failure risk of sub-capital Garden types 1 and 2 femoral fractures

Introduction: Sub-capital femoral fractures (SCFF) are impacted or non-displaced in Garden types 1 and 2, respectively. Non-surgical treatment is protected weight-bearing combined with physiotherapy and radiographic follow-up in selected patients. Traditionally, in situ pinning is the surgical treatment of choice. The aim of this study was to estimate whether the valgus deformity in Garden types 1 and 2 (AO classification 31B1.1 and 31B1.2) SCFF is a virtual perception of a posterior tilt deformity and if addressing this deformity improves patients’ outcomes. Materials and methods: The records of 96 patients with Garden Types 1 and 2 SCFF treated in tertiary medical center between 1/2014 and 9/2017 were retrospectively reviewed. They all had preoperative hip joint anteroposterior and lateral radiographic views. 75 patients had additional computed tomography (CT) scans. Femoral head displacement was measured on an anteroposterior and axial radiograph projections and were performed before and after surgery. Preoperative 3D reconstructions were performed for a better fracture characterization, and assessment of the imaging was performed by the first author. Results: The average age of the study cohort was 73 years (range 28–96, 68% females). There were 58 right-sided and 38 left-sided fractures. Ninety patients had Type 1 and six patients had Type 2 fractures. The average preoperative posterior tilt was 15 degrees and the average valgus displacement was 10 degrees on plain radiographs compared to 28 degrees and 11 degrees, respectively, on CT scans. Posterior tilt was found with a virtual perception as valgus-impacted fractures. The postoperative posterior tilt was corrected to an average of 3 degrees and the valgus displacement to 5 degrees. Conclusion: CT provides an accurate modality for measuring femoral head displacement and fracture extent. The posterior tilt displacement should be addressed during surgery to lower failure risk and the need for additional procedures. IRB approval: TLV-0292-15. Level of evidence: IV.