Abstract: A method and apparatus for sealing a defect in an annulus is provided herein. A plug made from a biodegradable or biocompatible polymer or a combination thereof can be used to seal the defect. The plug can include a cage with a sealed end and at least one retaining member on the outer surface. In one embodiment, the plug includes a hollow bore that is filled with a matrix of a growth-promoting compound. An aperture formed on the outer surface of the plug provides a pathway for surrounding cells to access the matrix. In another embodiment, a cap with a slot is provided at a second end of the plug. In still another embodiment, the cap is provided with no slot therein. Further, the plug may be inserted into the defect of the annulus by a tool. Additionally, a method using the plug is provided to seal the defect.