A method for treating a spinal disc comprises the steps of: determining the integrity of the annulus by subjecting the annulus to a first pressure applied internally of the annulus; providing access to the nucleus pulposus through the annulus without removing any tissue from the annulus or from the nucleus pulposus; and sealably injecting curable biomaterial through the annulus access directly into the nucleus pulposus at a second pressure correlated with the first pressure. The integrity of the annulus may be determined by a pre-operative discogram using a contrast medium that has a viscosity substantially similar to the viscosity of the biomaterial to be injected. The curable biomaterial may be injected under a pressure sufficient to distract opposing vertebral bodies communicating with the disc space.