Cervical (Neck) Implants used in Spine Surgery
Cervical implants are devices surgeons use to decompress and stabilize the spine. These devices are implanted either from the front (anterior) of the spine, or from the back (posterior). Information about anterior implants begins below.
The goals of cervical spine surgery include:
1. Reduce pressure on the nerve(s) by decompression (i.e., surgically removing tissues pushing on a nerve).
2. Stabilize the cervical spine by fusing 2 or more cervical vertebrae together.
Anterior Cervical Approach Implants
Interbody Cages or Spacers
Cages and spacers are placed between 2 vertebrae. Their purpose is to:
1. Maintain space between vertebrae (if the space gets too narrow, nerve roots can be pinched).
2. Preserve spinal alignment (e.g., a healthy neck has a specific curve; a spacer can help restore this curve) and/ or,
3. Promote spinal fusion (i.e., join (fuse) 2 or more vertebrae together).
Cages come in different shapes and sizes; some are cylinder-shaped and others box-shaped. Cages are placed (fit) into the spine between vertebrae. Usually, cages are made from bone, metal, plastic, or carbon fiber. Bone chips (autograft, allograft, other bone graft substitutes, or other bone growth stimulating substances (e.g., demineralized bone matrix) may be packed into the cage. During the months after surgery, the hope is the cage will allow (enhance) fusion between the vertebrae below and above. Fusion increases spinal stability.
Spacers are solid devices and bone cannot be packed inside. A spacer is used to help restore or correct spinal alignment.
Anterior Cervical Plates are attached to the front of 2 or more vertebrae. Plates help to:
1. Increase cervical spine stability immediately after surgery.
2. Stabilize the cervical spine during healing.
3. Increase the chances for a successful solid fusion.
4. Help reduce the time the patient may need to wear a cervical collar after surgery.
Plates are made with screw holes through which screws are placed into the adjacent (to be fused) vertebral bodies to anchor the plates into proper position. Both plates and screws come in different designs and sizes. Most plates are made from metal (mainly titanium); some are made from plastics. Certain newer plates are made from composite materials that dissolve after fusion occurs. Some plate designs are self-compressing to help promote spinal fusion.
Artificial Cervical Discs: Spine surgeons around the world are interested in cervical artificial discs to treat degenerative disease. It is believed maintaining motion between vertebrae is better than spinal fusion. Early studies report cervical artificial discs may help slow down, or prevent, adjacent level disc degeneration. The procedure is called disc arthroplasty. Artificial discs are made from various materials. Some designs are all metal and others metal and plastic composites. There are a number of on-going, and some completed, FDA trials of artificial discs underway in the United States. Devices are being cleared for sale and implantation as the studies demonstrate safety and efficacy compared to fusion in selected cases.
If your surgeon recommends cervical surgery, you can be encouraged that cervical decompression and stabilization procedures are some of the most successful operations spine surgeons perform today. Patients generally have rapid recovery and quickly return to activities of daily living with marked improvement of their symptoms.