Polyaxial bone screw
US9763700B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 14, 2016 |
| Grant date | Sep 19, 2017 |
| Priority date | — |
| Expiry date | Dec 14, 2036 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B17/8695
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A polyaxial bone screw for attaching a rod to a vertebra comprises a fastener having a threaded shank and a head. A yoke has a rod receiving channel for receiving the rod. A screw support rotatably attached to the yoke has a cavity articulatingly and rotatably supporting the fastener head, a hole receiving the threaded fastener shank therethrough, and a plurality of slots for maximum screw angulation. A crown has an upper rod receiving surface, a lower surface in contact with the fastener head and a projecting surface in contact with the yoke. A biasing element between the screw support and the yoke applies biasing forces among the fastener, the crown, and the yoke to provide sufficient friction to retain the yoke in a manipulable position relative to the fastener. A set screw is supported by the yoke overcome the bias and to rigidly secure the components.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.