1.   Currently, surgeons fuse vertebrae directly together after a disc is removed, either with or without a screw to stabilize the bond.

2.   Robertson is marching even though she just had a cervical disc removed.

3.   The implants are placed in the spine opening created after a damaged disc is removed, to help vertebrae move together.

4.   Holtz underwent surgery Tuesday to remove a disc in his neck that was bulging and compressing his spinal cord, causing weakness in his arm and leg muscles.