Artificial Discs: Spine Experts Speak Out
The approval in 2004 of an artificial disc to treat degenerative disc disease has had lots of people talking. Is it a cure for back pain or just another high-tech, high priced gadget? The answer probably lies somewhere between. SpineUniverse spoke to several renowned and respected spine specialists about their opinions of this new technology. Read on to find out what these experts think.
CHARITA Artificial Disc
DePuy Spine, Inc.
|Todd Albert, MD
Thomas Jefferson University
In October 2004, the CHARITÃ Artificial Disc (DePuy Spine, Inc.) was approved by the FDA for use in patients with single-level degenerative disc disease. Patients and physicians should keep in mind that while the safety and efficacy of this new technology has been demonstrated in a large, carefully done clinical trial, the long-term outcomes are not well known. We will certainly discover problems that occur with widespread use. Careful release of this technology is critical and superb understanding of the indications and contraindications are necessary.
One critical issue with disc replacement is that this procedure requires the expertise of a superb access surgeon. That surgeon has to be specifically trained at control of the iliac vessels especially at L4-5, where the vessels have to be taken across the entire spine for well-centered implantation of the artificial disc device. Correct sizing and positioning of the device is critical for best functionality and lowest chance of failure. If and when these devices fail, the revision surgery will be extremely difficult and fraught with potential dangers of vascular, visceral, or nerve injury.
The outcome results of the clinical trial are encouraging. However, patients and physicians should remember that all operations for back pain, even in the best of hands, carry a failure rate of up to 30% because of our lack of understanding of the pain generators. Given this fact, very slow and judicious integration of any new device or surgery for back pain should be undertaken.
|Edward Benzel, MD
The Cleveland Clinic Foundation
The recent approval of artificial disc technology for use in the United States is indeed a breakthrough and a landmark in modern medicine. I, however, have one major recommendation to physicians and patients alike—be careful!
The use of new technologies is guided by the published literature. The results of existing studies however, are heavily influenced by bias. The desire to achieve a good result by both the patient and physician are substantial. The placebo effect is often profound. Intellectual bias often clouds the picture. One has only to review the existing literature regarding other new technologies to witness the all too common phenomenon of the demonstration of initial enthusiasm, with subsequent failure or suboptimal clinical efficacy.
This was very graphically illustrated by the initial enthusiasm enjoyed by the threaded interbody fusion cage, which was subsequently squelched by the reality of long-term clinical trials.
Expensive and dangerous technologies, such as total disc replacement, place us all on a very slippery slope. Its utilization may benefit a small group of patients. But its use by overzealous and impulsive surgeons in eager patients may cause significant morbidity and even mortality and contribute to an economic drain that may threaten the existence of our medical system. To patients and treating physicians like, please be careful!
|John Carbone, MD
Orthopaedic Spine Surgeon
Harborview Reconstructive Spine and Orthopaedic Specialists
My personal opinion and concern regarding this new treatment option is as follows:
- While spinal implant technology continues to rapidly evolve, our current understanding of the complex problems of spinal disorders also continue to evolve. It appears that artificial discs such as the CHARITÃ Artificial Disc, which was recently approved by the FDA, will continue to become increasingly available for use by spine care professionals. While these new devices offer an exciting new treatment option, we must be sure that the benefits of these implants will continue for the life span of the patient.
- Patients, and doctors alike need to be cautions in embracing any new technology for which we have no long-term outcome data support.
- We also need to be concerned with how long these devices will last. Most of the patients who are candidates for this technology are the youngest population to ever receive orthopaedic implants. They need the longest endurance of any orthopaedic implant to date. The average age of patients who qualify for artificial disc replacement is around 35 years of age. Given current life span expectations, we will need these devices to function for 60 years, if not more. Unfortunately, there is no long-term data regarding this clinical scenario and the current data on the CHARITÃ Artificial Disc from European studies is quite limited. We have to be able to ensure our patients and our colleagues of the long-term safety of these products before we rush to implant them.
I do believe that this is only the first generation of implants and as the materials and technologies evolve, so will the devices that help ensure motion preservation of both the lumbar and cervical spine. Stay tuned.