Frictional polyaxial screw assembly
US8197517B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 2008 |
| Grant date | Jun 12, 2012 |
| Priority date | — |
| Expiry date | Dec 20, 2030 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B17/8805
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
Various embodiments are provided with a polyaxial spinal screw assembly that comprise a threaded screw having a bulbous or curvate head, and a receiver for receiving the head of the screw, and a slotted collet between the receiver and the screw head. The collet may, in an un-locked condition, bear against the head of the screw to frictionally retain the screw's angular position. The collet may have a lip that may engage with a corresponding internal feature of the receiver. The screw head may be able to be inserted into the receiver through the bottom of the receiver. The screw may be cannulated and also may be fenestrated. Embodiments may also include a bone screw having fenestration holes that include a component in the rotational direction, such as backward-facing with respect to the forward-rotational direction of the screw.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.