Hip Fractures: Relevant Anatomy, Classification, and Biomechanics of Fracture and Fixation

Abstract

Introduction: Hip fractures represent an important health-care dilemma, costing the US$ billions annually. Hip fractures can diminish quality of life and significantly increase morbidity and mortality if not properly treated. Recent research has brought forth new information regarding treatment as well as information on emerging complications seen within the fixation constructs themselves. Significance: Understanding the pathoanatomy of hip fractures and the biomechanics of surgical fixation constructs is critical for successful treatment. In this article, we review the relevant anatomy and classification of femoral neck and intertrochanteric fractures. Furthermore, the biomechanics of hip fracture fixation strategies as well as implant-related complications are addressed. Results: Even though laboratory testing demonstrated that intramedullary nails have greater biomechanical stability, the clinical results between fixation constructs have been similar when the chosen implant (ie, sliding hip screw vs cephalomedullary nail) has been correctly applied to the specific fracture pattern. Recently, data have shown that when using cephalomedullary nails, there is potential for increased failure with cutout when using the helical blade versus the lag screw, with majority being the atypical “medial cutout.” Conclusion: The goal of surgical treatment of hip fractures is surgical treatment that allows for early mobilization and weight bearing. A full understanding of the anatomy and fracture characteristics will allow the surgeon to correctly apply the right implant to allow for uneventful healing. Surgeons need to be aware, however, of complications that can arise when using specific implants. Further research is ongoing to further determine the treatments that will allow optimal cost-effective care for the geriatric patient with hip fracture.