LLUMC participates in lower back pain study
Wayne Cheng, MD, the orthopaedic surgeon who heads the spine service at Loma Linda University Medical Center, points to a location on a model of the human spine where he and his colleagues will implant the Total Facet Arthroplasty System during a clinical trial of the new procedure at the Medical Center.
Loma Linda University Medical Center has been chosen as a test site for the clinical study of a promising new surgical procedure to help people with chronic lower back and leg pain. According to Wayne Cheng, MD, the orthopaedic surgeon who serves as head of the spine service at LLUMC and the study’s primary investigator, the clinical trial will evaluate the safety and effectiveness of the Total Facet Arthroplasty System, or TFAS—a promising new alternative to conventional spinal fusion surgery. TFAS was developed by Archus Orthopedics of Redmond, Washington.
TFAS offers patients a number of important advantages. “The potential benefits to our patients include immediate relief of pressure on the spinal nerves, maintenance or improvement in motion between the treated vertebrae, and perhaps, more immediate relief of symptoms compared to the alternate treatments available,” Dr. Cheng notes. It also eliminates the need for doctors to perform an additional surgical procedure in which they harvest bone from the patient’s hip for the bone graft required by spinal fusion.
Dr. Cheng points out that the TFAS device treats lower back and leg pain caused by moderate to severe spinal stenosis and/or grade one spondylolisthesis. Spinal stenosis, the degenerative narrowing of the spaces in the spine, can lead to spinal cord or nerve root compression while spondylolisthesis is vertebral slippage due to age-related deterioration.
The new TFAS implant has the potential to stabilize the affected vertebrae without rigidly fusing the joint or removing the inter-vertebral disc. TFAS is designed to allow patients to maintain a quality of motion similar to what they enjoyed before the onset of debilitating back and leg pain.
Dr. Cheng is confident the new TFAS procedure will result not only in a loss of back pain, and the radiating leg pain that often accompanies it, but also in increased freedom of movement following surgery. He notes that physical therapy and other non-invasive therapies—including traction, body casts, braces, medications, or just doing nothing to see if the problem clears up on its own—are often the first line of defense against chronic lower back and leg pain. However, since those methods don’t always resolve the pain, doctors frequently resort to spinal fusion—a practice that involves removing the offending discs and fusing the remaining vertebrae together.
Although spinal fusion often does relieve pain, it frequently impairs the patient’s ability to move. Fortunately, the new TFAS procedure not only eliminates pain, it also allows the patient to move freely without restriction.
“The process of implanting TFAS into the patient’s spine is very straightforward,” says Dr. Cheng. “The surgical approach is similar to spinal fusion, but the outcome is usually dramatically different. With its ability to perform a more complete decompression of the impinged nerve roots, and to implant a device that has potential to restore natural motion, I expect my patients to be back on their feet shortly after the surgery.”
Over the next year, selected surgical sites throughout the United States, including Loma Linda University Medical Center, will implant the TFAS device as part of a large clinical study. Dr. Cheng is one of a select group of prominent American spine surgeons who have been chosen to participate in the investigation.
The clinical study is an important step toward establishing TFAS as a new treatment option for patients in the United States. It has been successfully used in Europe since 2005, but due to the strict guidelines of the U.S. Food and Drug Administration, the procedure must first be evaluated in an FDA-approved study, such as the one underway at Loma Linda.
Dr. Mark Reiley, the orthopaedic surgeon who founded Archus Orthopedics, Inc., commented on the potential of joint replacement in the spine by noting that “40 years ago, we used to fuse hips. Patients and surgeons universally recognize that spine fusion is an archaic therapy, but unfortunately, it’s been the only option available. Just like hips and knees, joint replacement is where we are going in spine care.”
The TFAS study is not the only one Dr. Cheng and his colleagues are pursuing. They have currently applied for permission to participate in five additional clinical trials, all aimed at improving spinal therapy options for patients. Previous studies Dr. Cheng has participated in include research into Kineflex single-level total artificial disc replacement, degenerative disc disease, spinal stabilization, spinal fusion, and other topics related to improving spine health and function.
“I take pride,” he notes, “in solving difficult spinal disorders. I enjoy helping my patients through surgical and non-surgical treatments. I know I speak for all the members of our team when I say we are excited about the promise TFAS offers for patients who suffer from chronic lower back and leg pain.”
The clinical investigation at Loma Linda got underway when doctors first performed the TFAS procedure on a patient here on April 3, 2007. Dr. Cheng estimates that he and his team will wrap up the TFAS study by mid-2009.
By James Ponder