Hydrogel intervertebral disc nucleus with diminished lateral bulging
US5534028A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 1993 |
| Grant date | Jul 9, 1996 |
| Priority date | — |
| Expiry date | Apr 20, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S606/91
- WIPO fieldMedical technology
- WIPO sectorInstruments
Abstract
A prosthetic nucleus for a vertebral disc is made of a hydrogel material. The hydrogel prosthetic nucleus has a shape generally conforming to the natural nucleus pulposus, and it exhibits diminished lateral bulging under high compressive loads. The hydrogel has a water content of from 30% to 90% and has a compressive strength of 4 MNm.sup.-2 or greater. When the hydrogel material is dehydrated, it has a dimension of less than half of that of the hydrated hydrogel nucleus. The prosthetic nucleus may be formed of two or more pieces of hydrogel material which pieces, when combined, have a shape generally conforming to the natural nucleus. The prosthetic nucleus may have a stiff posterior periphery and/or a thickened anterior wall.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.