A cutting instrument for use in the complete removal of the annulus fibrosus of an intervertebral disc contains a curvature in the shaft. The curvature forms a guide that rests upon an intervertebral disc and guides the cutting head around the circumference of the intervertebral disc. The curvature of the shaft of the instrument conforms to the circumference of the intervertebral disc and prevents vessels and extra spinal tissue surrounding the intervertebral disc from being damaged particularly when cutting the posterior portion of the intervertebral disc where visibility is minimal. The cutting instruments contain blunt blade guards further minimizing any potential damage to tissue surrounding the intervertebral disc.