USC Neurosurgery is the first Los Angeles center to be performing total facet replacements with the Total Facet Arthroplasty System (TFAS). In cooperation with Archus Medical Devices (Redmond, Washington) and the Food & Drug Administration (FDA), USC neurosurgeons are implanting the novel device in an Investigational Device Exemption Trial. Patients eligible for the trial have lumbar spinal stenosis unresponsive to nonsurgical, conservative treatment modalities.
The device replaces the facet joints, small synovial joints which are important for spinal motion and stability, but which often overgrow and compress on the nerves in the low back. Traditional surgical treatments involve removal of some of the facet joint and surrounding bone with a common surgical procedure known as a laminectomy. However, the removal of this bone can result in destabilization and collapse of the lumbar spine. For this reason, many surgeons will also perform a spinal fusion after the laminectomy. While the laminectomy and fusion are effective, fusion of the spine can reduce natural motion and may even accelerate degeneration or arthritis of the spine at other neighboring segments of the spine. The TFAS device preserves spinal motion, stabilizing the treated region but potentially preventing the unintended consequences of spinal fusion.
Study investigators Thomas Chen, MD, Charles Y. Liu, MD, PhD and Srinath Samudrala, MD have found the device to be efficacious to date, and the FDA will be reviewing the study outcomes for the next three years. It is anticipated that the TFAS may become available for general use in the United States in 2019.