Lower Bone Mineral Density is Associated with Intertrochanteric Hip Fracture

Background: A better understanding of how bone mineral density and vitamin D levels are associated with femoralneck and intertrochanteric hip fractures may help inform healthcare providers. We asked: 1) In patients age ≥ 55 years,is there a difference in quantitative ultrasound of the heel (QUS) t-score between patients with fractures of the femoralneck and those with fractures of the intertrochanteric region, accounting for other factors 2) In patients age ≥ 55 years,is there a difference in vitamin D level between those with fractures of the femoral neck and those with fractures of theintertrochanteric region, accounting for other factors? 3) Is there an association between vitamin D level and QUS t-score?Methods: In this retrospective cohort study, 1,030 patients were identified using CPT codes for fixation of hip fracturesbetween December 2010 and September 2013. Patients ≥ 55 years of age who underwent operative management fora hip fracture following a fall from standing height were included. Three orthopaedic surgeons categorized fracture typeusing patient radiographs. Upon hospital admission, QUS t-scores and vitamin D levels were determined. Descriptivestatistics, bivariate analyses and multivariable regression were performed.Results: Accounting for potential confounders, patients with lower QUS t-scores were more likely to have intertrochantericfemur fractures than femoral neck fractures. In a bivariate analysis, there was no association between vitamin D leveland either fracture type. There was no association between vitamin D level and bone mineral density.Conclusion: Patients with lower bone density that fracture their hips are more likely to fracture in the intertrochantericregion than the femoral neck, but vitamin D levels are unrelated. Awareness of this association emphasizes theimportance of bone mineral density screening to assist with intertrochanteric hip fracture prevention.Level of evidence: III