Currently there are great advances being made in the surgical treatment options for patients with low back pain that has not resolved with non-operative treatments. These surgical options are oriented toward motion-retaining devices such as artificial discs, and posterior instrumentation designed to relieve the patient's pain by providing controlled motion to the problematic spinal segment. Many new implants will be introduced in the next few years. The DePuy Charité Artificial Disc is an example of such a device recently presented to the FDA Review Panel and awaiting final FDA approval. Other lumbar total discs being tested include: Synthes' PRODISC; Medtronic's Maverick; and Stryker's FlexiCore. We at the Texas Back Institute are participating in three of these clinical trials and are pleased with the results to date. [Editorial note: As of August 2006, both the DePuy Charité lumbar artificial disc and the Synthes' PRODISC-L have been approved by the FDA. Other total disc replacements will likely soon receive approval and be available to patients as well.]
The process to bring such devices to market is long and strictly regulated by the Food and Drug Administration (FDA). The FDA's responsibility is to ensure that new devices are at least as safe and effective as the current standard of care for the condition being treated. During the FDA-regulated studies, there are strict rules and guidelines that must be followed, especially in the areas of patient selection criteria and surgeon training.
Patient selection criteria
In these FDA-regulated studies, the inclusion/exclusion criteria are rigorously defined to create a homogeneous group of patients and also to rule out patients who may be at the greatest risk of complications if the new implant were to be used. Surgeons must carefully adhere to the inclusion and exclusion criteria when selecting patients for the study.
The surgeons participating in such studies are usually selected due to their high level of training, expertise, and frequently have experience with a similar device or operative technique. These investigators will also have a record for abiding by the study protocol in terms of adhering strictly by the patient selection criteria, implanting the devices in the fashion for which they were designed, and the technical skills to execute the device implantation correctly. In order to be a physician/investigator in this type of clinical trial, not only are surgeons selected who already have the requisite technical skills, but the manufacturer provides training to the surgeons. This generally involves the surgeon attending a training session on both the study protocol and information about the instrumentation to be used for implanting the device. The training then progresses to the surgeon working with the instruments in a plastic model or cadaveric spine model. The surgeon then observes an expert implanting the device into one or more patients. The next step is for the investigator to implant the device with the expert surgeon at his side to advise and assist if necessary.
The clinical trial is executed under these stringent guidelines for patient selection and surgeon technique. After the data collection is complete, generally involving following all patients for a minimum of two years, it is submitted to the FDA for them to determine if the new device is at least as safe and effective as the current standard of care for the same condition. After the FDA gives a manufacturer permission to market a device, the stringent regulations employed during the trial do not have to be enforced any longer.
The extent of training for a surgeon to use a new technology has varied greatly in past years. Some have pursued a level of training of similar to that employed for the FDA trial. Unfortunately, this is always not the case. There are currently no well defined, accepted standards for the training of surgeons wanting to employ the use of new technology. As the availability of new technologies increases, and the patient demand for such increases, the number of surgeons entering the realm of new technology will undoubtedly increase. There is a chance that some of these new users will not yet be familiar with similar procedures and will require more training for them and their operating room assistants.
With the explosion of new technologies in spine, one society, the Spinal Arthroplasty Society, has set a goal of establishing standardized training programs for physicians prior to their using new technologies. The training would be similar to that required for participation in the FDA trials. While such training is expensive and time consuming for both the surgeons and faculty, there are many benefits for patients, surgeons, hospitals, and manufacturers.
As always, patients should ask questions any time their doctor suggests undergoing surgery. In order to make an educated decision when giving consent to have spine surgery, the patient should feel that they have a comfortable knowledge of treatment options, potential risks and complications of the proposed surgery, and a plan for recovery from the surgery.
With respect to new technology such as the artificial disc, the patient needs to specifically ask about the type of training the surgeon has undergone, how many cases he or she has performed with that specific device and/or with similar devices. If a surgeon is uncomfortable or hesitant answering such questions, it may be advisable for the patient to seek a second opinion.
There are many new treatment options emerging for the treatment of patients with back pain that does not resolve with non-operative measures. However, even the best designed devices may not produce the desired results if rigid patient selection criteria and surgical technique are not employed. Efforts are being made to standardize the training for surgeons in the use of new technologies. This can only be beneficial for all involved, including surgeons, hospital, manufacturers, and especially the patient. Patients should also feel comfortable asking questions about the surgery, treatment options, and the type of training and the number of similar cases the surgeon has performed. With appropriate surgeon training and patient selection, the true goal of improving the lives of patients can be realized.