Zimmer Biomet Holdings developed first-of-its-kind tether, Vertebral Body Tethering (VBT) device, to correct idiopathic scoliosis in children and adolescents who fail to react to conservative treatment options, such as external bracing. This device has been approved by The U.S. Food and Drug Administration.
The Tether consists of a flexible cord connected to a system of vertebral screws and anchors. The screws of the system are placed on the same side of each vertebra in the curved section of the spine.
During the surgery, the tension applied to the tether compresses the side to correct the patient's spinal curve. The implant is positioned using a minimally invasive approach through small incisions on the side of the patient's chest.
The tether slows growth over-time on the curved side of the spine and promotes growth on the opposite side. The device is designed to continue to correct the curvature as the patient grows while allowing a greater range of motion.
The Tether system is an alternative to spinal fusion surgery, which uses rods and screws to fuse the vertebrae to correct the curvature in scoliosis patients.
Even though spinal fusion is often successful, but it permanently restricts the spine motion and may have long-term complications such as arthritis, pain, and future spinal deformities, which could require additional surgical treatment. The spinal fusion remains an option for patients whose curves are not adequately corrected with the VBT device.
Some of the serious adverse events observed with the tethering procedure include tether breakage, overcorrection of the curvature, pneumothorax or air leakage into the space between the lung and chest wall.
Besides these, general complications consistent with spinal surgery were also seen, including pain, nerve injury, respiratory problems, and bleeding.
Idiopathic scoliosis is best defined as the sideways curvature of the spine. It is one of the most common spinal deformities in children and is often diagnosed between ages 10 to 18. However, its cause is unknown.
