A method of repairing a defect in an annulus fibrosus of an intervertebral disc, without excising the entire nucleus pulposus of the disc. The method includes inserting an introducer needle through the annulus fibrosus by puncturing the annulus fibrosus with the introducer needle, injecting an in situ curable, bio-compatible polymerizable or polymeric material composition into the disc through the introducer needle directly or indirectly so that the in situ curable composition contacts a defect in the annulus fibrosus; and curing said material in situ.