Double-threaded bone screw with segmented anchoring profiles

The thread structure is segmented into multiple distinct sections along the screw length: a first section with a first pitch, a second section with a second pitch, and a third section with a third pitch. Each section is optimized for different bone densities, with coarser pitches for denser cortical bone and finer pitches for less dense spongy bone, thereby improving anchoring reliability without requiring a completely complex new design

Different portions of the screw thread are given different local qualities through varying pitch values. The first section near the tip has a first pitch suitable for penetrating and anchoring in dense cortical bone, the second section has a second pitch for transitional bone density, and the third section has a third pitch for less dense spongy bone. This local differentiation of thread properties optimizes performance across varying bone densities

The uniform thread pitch is segmented into multiple distinct pitch zones along the screw length. The first section has a first pitch optimized for cortical bone engagement, the second section has a second pitch for transitional zones, and the third section has a third pitch for spongy bone engagement. This segmentation enables adaptability to different bone components while maintaining manufacturability through standardized threading processes

The thread pitch parameter is changed at different sections of the screw to adapt to varying bone densities. The first pitch is coarser for cortical bone, the second pitch is intermediate, and the third pitch is finer for spongy bone. These parameter changes are implemented through controlled manufacturing processes that can produce multi-pitch threads with adequate precision

The penetration process is segmented into phases corresponding to different bone layers. The first section with its pitch is designed for controlled penetration into cortical bone, the second section provides a transition zone, and the third section with its pitch is designed for engagement in spongy bone. This segmentation allows the screw to achieve deep anchoring strength while the varying pitches help control the penetration force and reduce the risk of excessive bone damage

The thread pitch parameter is changed to match the mechanical properties of different bone layers. The first pitch is optimized for cortical bone penetration and engagement, the second pitch for transitional zones, and the third pitch for spongy bone engagement. These parameter changes allow the screw to achieve adequate anchoring strength in each bone layer while minimizing the harmful effects of excessive penetration forces