Biomechanical comparison of bone-screw–fasteners versus traditional locked screws in plating female geriatric bone

•Nonlocking bone–screw–fasteners (BSF) are designed with screw threads interdigitate in the bone and can be compared to traditional locking buttress threaded screws which couple to the plate.•In plating female geriatric bone, bone–screw–fasteners may provide comparable stability to traditional locking screws with the added ability to generate compression at the plate-bone interface.•Surgeons can consider utilizing bone-screw-fasteners to optimize screw purchase, especially in poor bone quality or short fracture segments. To biomechanically compare plated constructs using nonlocking bone–screw–fasteners with interlocking threads versus locking screws with traditional buttress threads in geriatric female bone. Eleven matched pairs of proximal and distal segments of geriatric female cadaveric tibias were used to create a diaphyseal fracture model. Nonlocking bone–screw–fasteners or locking buttress threaded screws were applied to a locking compression plate on the anterolateral aspect of the tibia placed in bridge mode. Specimens were subjected to incrementally increasing cyclic axial load combined with constant cyclic torsion. Total cycles to failure served as a primary outcome measure, with failure defined as 2 mm of displacement or 10 degrees of rotation. Secondary outcome measures included initial stiffness in compression and torsion determined from preconditioning testing and overall rigidity as determined by maximum peak-to-peak axial and rotational motion at 500 cycle intervals during cyclic testing. Group comparisons were made using paired Student's t-tests. Significance was set at p