Zimmer Biomet

Mobi-C was the first cervical disc approved for both one- and two-levels in the United States and is backed by clinical data that proves superiority to two-level ACDF through seven-year follow-up. 

The Mobi-C Cervical Disc is designed to provide pain relief and allow for the normal biomechanical function of a diseased spine level after disc excision. The kinematic principle behind the Mobi-C design is to allow for a normal range of motion in the cervical spine and to enable or re-establish the physiological mobility of the targeted disc space through the mobile core design. This biomechanical and kinematic concept is designed to preserve the instantaneous axis of rotation of the affected disc space.

Mobi-C eliminates operative steps with no bone chiseling required to cut a path for teeth or screws. After disc preparation, Mobi-C can be inserted in one step. Mobi-C comes preassembled on a plastic cartridge. This simplifies implantation and allows an X-ray view of the implant for optimal positioning.

The Tether is a new treatment option available to patients with scoliosis. It is the first and only FDA-approved Vertebral Body Tethering system. Historically, if bracing didn’t work, the only other option was spinal fusion, which involves implanting metal rods along either side of the spine to straighten the curve. The Tether is different because the spine is still able to bend and flex, rather than being fused or fixed in place. The Tether’s strong, flexible cord applies pressure on the outside of the curve, allowing the inside of the curve to continue growing. Via a process called “growth modulation,” the patient’s unimpeded natural growth continues to repair the curve and straighten the spine. Since Vertebral Body Tethering allows the spine to continue bending and flexing even after treatment, patients who find it important to maintain motion of their spine may be particularly interested in The Tether.

Regulatory Approval

The Tether System is a special category of medical device called a Humanitarian Use Device (HUD) which means that it has been shown to have probable benefit. The Tether is appropriate for treating idiopathic scoliosis in young people who have scoliosis with a significant amount of growth remaining.

Clinical Study Results

Spinal tethering is being studied in a clinical trial of scoliosis patients (48 girls and 8 boys) who had a spinal tethering surgery when they were around 12 years old. Patients enrolled in the study see their doctor regularly for follow-up appointments until they are fully grown (approximately 18 years old). On average, patients in this study saw the Cobb angle (an angular measurement of the curvature of the spine) reduce by more than 50%, from 40.4° to 17.6°. A Cobb angle of 10° is the minimum angle for a diagnosis of scoliosis. Patients also saw a reduction in the size of their rib hump prominence from an average of 13.6° to 8.7°. Following surgery, fewer patients on average reported unlevel shoulders and unlevel hips. This study shows that there is a likely benefit of surgery with The Tether - Vertebral Body Tethering System, however, complications are possible. Potential patients with questions should ask their doctor for more details about the clinical study and its results.