Some lumbar spine conditions may require surgery. There are many different spine surgery procedures and specific options for cases in which lumbar spine surgery is needed. One type of surgery is total disc replacement. This article covers lumbar arthroplasty using an Artificial Disc.
Goals of Lumbar Arthroplasty
The goals of lumbar total disc replacement are to:
- Maintain segmental spinal motion
- Provide pain relief and allow patients to increase activity
- Restore disc height and lordosis, or curvature of the spine
- Eliminate postoperative fusion problems, such as bone graft donor site pain and pseudarthrosis, or "false joint," which is an unhealed part of a bone that moves like a joint
Disc Design and Research
Preclinical testing indicates that the unique mobile-core design of the Artificial Disc is intended to mimic the motion of the operative spinal segment, maintain segmental stability, restore proper disc height and re-establish the proper curvature of the spine.
A fixed-core design, on the other hand, has a fixed axis — or nonfloating — center of rotation. This type of design means that translation — or movement — is never independent from rotation.
In biomechanical testing, the Artificial Disc was shown to preserve the kinematics — or movement — of the intact disc. The mobile core reproduces natural movement between the segments of the spine, which is independent of rotation. The mobile core reproduces natural floating center of rotation.
Other research showed the Artificial Disc mimicked the intact spine in distribution of motion at both the operative and adjacent levels. The study suggested also that natural motion may reduce adjacent-level disease, which are problems that can occur after spine surgery.
Other research shows that the design may protect facet joints, those that make bending and twisting of the spine possible, and may reduce wear.
24 Months After Surgery
At 24 months, the Artificial Disc was demonstrated to be safe and effective for degenerative disc disease for patients with level 1 conditions from the L1 through S4 segments of the lumbar spine.
Read more about lumbar spine anatomy on our blog.
The Artificial Disc also rated high on patient satisfaction, with 74 percent of patients with the Artificial Disc were satisfied versus 53 percent of spinal fusion patients.
After two years, the Artificial Disc maintained motion. It allowed segmental spinal motion at the operative level versus loss of motion for the fusion patients. Patients experienced improvement in pain and function.
According to the Wilcoxon Rank Sum Test, patients treated with the Artificial Disc had statistically better clinical outcomes among those with spine surgery procedures. If older patients are otherwise indicated for total disc replacement lumbar spine surgery, the factor of age alone was found to have no effect on the clinical outcome for those up to age 60.
More post-surgery research results
In an analysis of patients five years after implants, there were significant difference in survivorship: The Artificial Disc at 93.41 percent versus the fusion group at 80.1 percent.
Other research found high patient satisfaction at 75 percent good or excellent results. The same study also found that the discs maintained their heigh and experienced no complications or loosening of the core.
In another survey, 100 patients with a minimum 10-year follow-up reported:
- Excellent patient satisfaction
- 90 percent good or excellent results
- Motion preservation
- Quality of life that included a 92 percent return to work
- Minimal adjacent-level disease, with only 2 percent adjacent-level disease
If you're going to have spinal surgery, there are steps you can take to be prepared for a successful procedure and recovery.