High-speed x-ray characterizes fracture incidence and bone-implant motion during a fall from standing

Abstract

Background: Fall-related traumas like hip fracture are a common yet devastating injury with poor outcomes. Characterizing fracture biomechanics and bone-implant kinematics is essential to increase our understanding of these events to inform treatment and prevention strategies.

Methods: This study developed a bilateral high-speed x-ray methodology for the real-time capture of fracture and kinematic data near the hip during fall impacts. High speed x-ray was applied to capture fall impacts of seven cadaveric pelvis-femur specimens encased in a soft tissue surrogate, using a previously developed method. In these specimens, the intact proximal femur had been prophylactically reinforced with an intramedullary nailing system intended to prevent fragility fractures. The feasibility of extracting 3D kinematic data from x-ray data was investigated.

Findings: The HSXR system demonstrated visual clarity and sufficient resolution for capturing skeletal fracture and kinematics. The data in this study revealed fracture and newly-seen deformations of the pelvis, highlighting the ability of the x-ray system to document real-time fracture and kinematic events. Kinematic data in 3D was extracted with sufficient accuracy for one specimen.

Interpretation: These results demonstrate the merit of high-speed x-ray for studying periprosthetic fracture, which is of increasing relevance due to increasing populations with orthopedic hardware. Application of this method advances our understanding of impact-related biomechanics and fracture mechanics during a clinically-relevant fall from standing.

Keywords: Fall impact; Fracture; High-speed x-ray; Hip; Prophylactic augmentation.