05192326 is referenced by 639 patents and cites 6 patents.

A prosthetic nucleus for implantation in the disc space after removal of a damaged or degenerated nucleus is formed from a multiplicity of hydrogel beads having a water content of at least 30%. The beads are covered by a semi-permeable membrane. The membrane has porosity less than the size of the beads to thereby retain the beads therein but permit fluids to flow in and out of the prosthetic nucleus.

Title
Hydrogel bead intervertebral disc nucleus
Application Number
633711
Publication Number
5192326
Application Date
September 9, 1991
Publication Date
March 9, 1993
Inventor
Paul A Higham
Ringwood
NJ, US
Qi Bin Bao
Livingston
NJ, US
Agent
Raymond W Augustin
Lawrence C Akers
Peter C Richardson
Assignee
Pfizer Hospital Products Group
NY, US
IPC
A61F 2/44
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