Advanced polyaxial locking hook and coupling element device for use with top loading rod fixation devices
US5609593A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 13, 1995 |
| Grant date | Mar 11, 1997 |
| Priority date | — |
| Expiry date | Oct 13, 2015 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61B17/7034
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A hook device for use with support rod implantation apparatus, having a rod receiving body polyaxially mounted to a blade portion such that the body may be polyaxially manuevered relative to the blade, for easy rod coupling. The blade portion has a semi-spherical head portion which sits above the lamina. The rod receiving portion is a separate coupling element having lower and upper portions. The lower portion is slotted and tapered, and has a semi-spherical interior chamber in which the semi-spherical head is initially polyaxially disposed. The upper portion has a pair of upwardly extending members, defining therebetween a channel for receiving the rod. The uppermost parts of the upwardly extending members include an threading for receiving a top locking nut. A locking ring is disposed about the coupling element, substantially below the side recess; the top of the coupling element being initially positioned above the lower ledge of the side recess such that the rod, when initially disposed therein, seats against the top surface of the locking ring. When the rod is in place, the top locking nut is tightened to provides a downward force onto the rod. The rod, in turn, applies a forc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.