Patent ID: 8506633

Claim:
A method for treating an intervertebral disc having a nucleus pulposus and an annulus fibrosis, using one or more polyelectrolyte materials, comprising: introducing the polyelectrolyte materials and an additive into the intervertebral disc space having an intact and competent annulus fibrosis without removing nucleus pulposus or annulus fibrosis material, thereby rehydrating the intervertebral disc space, wherein the polyelectrolyte materials are not more than about 15% crosslinked, thereby having a low gel strength, and are capable of attracting an amount of fluid at least about ten times the weight of the polyelectrolyte materials in their dry form under atmospheric pressure, wherein polymer chains comprising the polyelectrolyte materials are cross-linked after polymerization of the chains by reaction with a cross-linking agent; mixing the polyelectrolyte materials and the additive with a non-aqueous fluid to make the polyelectrolyte materials and the additive flowable; using a delivery device to inject the flowable polyelectrolyte materials and the additive into the disk space; and injecting a cross-linking agent into the disk space to react with the polyelectrolyte material and the additive to form an aggregate cross-linked material within the disk space comprising the polyelectrolyte materials and the additive cross-linked by the cross-linking agent.