Cervical Artificial Disc Replacement
Anatomy and Pathology of the Neck
The cervical spine has discs between each bone that provide cushioning for movements and body loads. The discs and bones in a healthy neck allow bending from side to side and front to back, and turning left to right. Disc problems can start from over-use, an accident, or just the wear and tear of daily life. Degenerative changes in the discs may result in damage that can cause pain. When a disc degenerates it can have tears or cracks that lose water, which cause it to become thinner and provide less padding to absorb movement. Degenerated discs can also bulge (herniate) and pinch the spinal cord or nerves, which causes loss of feeling, weakness, pain, or tingling down the arms and hands.
Before artificial discs were available, patients would often receive an Anterior Cervical Discectomy and Fusion (ACDF) procedure to alleviate the pain from a herniated disc. In a fusion surgery, the disc is removed and either a bone spacer or a plastic implant will be placed in the disc space to restore disc height and remove pressure on the pinched nerves or spinal cord. A metal plate and screws can be placed on the front of the neck to hold the implant in place. The potential downside of a fusion procedure, in addition to the loss of motion, is that it can create additional stress on the spinal levels above and below it. However, if a patient has degeneration in vertebrae adjacent to the impacted disc a ACDF will be the most likely course of action. Artificial disc replacement is ideal when a patient only has degeneration of the discs and the surrounding vertebrae are healthy.
Indications for Surgery
Artificial Disc Replacement is intended for adult patients (skeletally mature) with arm pain and/or neurological symptoms (such as weakness or numbness) with or without neck pain at one or two adjacent levels from C3 – C7 in the cervical spine. Patients should have failed non-surgical care (such as physical therapy or medications) for at least 6 weeks, or shown signs of progressively worsening symptoms. Disc damage needs to be confirmed by a doctor’s review of CT, MRI, or x-ray images. A doctor should always be consulted for proper indications and use of Mobi-C.
Artificial disc replacements like the Mobi-C provides bone sparing fixation without chisel cuts into the small vertebral bodies of the cervical spine. Other discs achieve their fixation by drilling keel cuts or screw holes into the bone, which can prevent safe implantation at two levels. Mobi-C was designed without a keel and therefore to be specifically applicable for both one and two-level indications. As of October 2015 Mobi-C is the only cervical disc replacement that has been approved by the FDA for two level replacement. This is where the added mobility of an artificial disc is truly felt by the patient. Typically a one level fusion will lead to minimal movement two level fusion tend to reduce cervical movement more. Artificial discs preserve a greater amount of movement. Another advantage of artificial disc treatment is it usually allows the patient to return to work sooner.
Currently Dr. Lynn Gaufin is the only neurosurgeon in Utah County that is trained to preform two level artificial disc replacement.