Polyaxial bone anchors with pop-on shank, fully constrained friction fit retainer and lock and release insert
US8998959B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Oct 19, 2011 |
| Grant date | Apr 7, 2015 |
| Priority date | — |
| Expiry date | Jan 20, 2032 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B17/7032
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A polyaxial bone screw assembly includes a threaded shank body having an integral upper portion receivable in an integral receiver, the receiver having an upper channel for receiving a longitudinal connecting member and a lower cavity cooperating with a lower opening. The receiver can have crimp tabs, but is devoid of spring tabs and collet-like flexible structures. A down-loadable compression insert (some with lock and release feature), a down-loadable friction fit split retaining ring having super structure for temporary friction fit with an up-loadable shank upper portion cooperate to provide for pop- or snap-on assembly of the shank with the receiver either prior to or after implantation of the shank into a vertebra. The shank and receiver once assembled cannot be disassembled.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.