Instrumentation, the use of plates and screws, has been developed specifically to increase the stability to the spine and to improve rates of successful spinal fusion. Because bone tends to fuse more effectively in an environment where there is little motion, instrumentation works by limiting the motion at the fused segment.

Anterior cervical instrumentation is used to hold the motion segments of the neck together so that they can fuse. The surgery is performed from the front of the neck and is most commonly used for treatment of cervical disc herniation, degeneration and fractures. Cervical instability can result from trauma, congenital deformity, or spinal reconstruction. Pseudoarthrosis, or the nonunion of bone (e.g. fracture), is another cause of cervical instability.

The cervical plate keeps the bone graft in place and provides stability between the vertebrae above and below the graft site. This stability facilitates fusion - a joining of bony structures. Cervical plates enhance the rate of fusion and, in some cases, may reduce the need for external bracing following surgery.

Titanium is the metal of choice for many spinal implants including plates and screws because it has a high resistance to corrosion and fatigue, and is MRI compatible.

After the disc is removed for an anterior cervical disc herniation, a space remains between the vertebral bodies. In the past, when no fusion was performed, this space collapsed and resulted in deformity and later increased risk of neck pain and/or pinching of the nerves. Due to the risk of disc space collaspe and later pinching of the nerve, the disc space can be fused, either with the patients own bone or bone from a bone bank. Instrumentation, plates and screws, may be used to hold this construct together until it heals. The plate and screws are shown (image at left) holding the vertebral bodies together so that the bone grafts do not slip out and so that the bone can heal.

Putting a plate in on a single level procedure does require a little more dissection and operating time. Anterior plates were developed in the 1980's and their use was initially restricted to long fusions (multi-level fusions). The risks of placement of the plate are minimal, but the principal disadvantage is that they are expensive. Because they are expensive and there is no compelling evidence that they are needed for one-level fusions, there is still considerable controversy surrounding whether or not every patient should receive a plate. Despite the controversy, more surgeons are also using them for single level procedures due to the increased stability that they confer, and the ability to reduce the need for external bracing.