Failure Characterization of Human Cancellous Bone During Screw Pull-Out¶
Benjamin Schnabel (HLRS)
Abstract¶
Osteoporosis is a systemic skeletal disorder characterized by reduced bone mass and deterioration of bone microarchitecture, leading to increased fragility and fracture risk. In Germany, approximately 6.3 million individuals are affected, with a growing incidence of osteoporosis-related fractures, especially proximal femur fractures, as life expectancy increases. Surgical treatment for fractures often involves internal fixation using screws; however, failure rates for screw fixation range from 13% to 18.2%, with complications such as screw cut-out, mechanical failure, and aseptic loosening. These complications, which are caused by a reduction in bone strength and other factors, impact the fixation and durability of bone screws. An important indicator of implant stability is the pull-out strength of a screw, defined as the maximum force required for extraction. This study aims to characterize the failure behavior of human cancellous bone during screw pull-out, focusing on the mechanical properties and factors influencing stability using finite element analysis to simulate mechanical behavior.