Safety Outcomes of Vertebral Body Tethering Technique

Scoliosis is a condition where the spine is deformed by a curvature in the coronal plane. It is generally associated with a twisting (axial plane) deformity as well. Curves between 10 and 25 degrees are considered mild. Curves between 25- and 50 degrees are classified as moderate. Curves greater than 50 degrees are termed severe. The current standard of care for moderate Adolescent Idiopathic Scoliosis(AIS) in patients with remaining growth is to utilize a thoracolumbosacral orthosis (TLSO brace) to prevent progression of deformity. The scientific evidence has supported the efficacy of this intervention in avoiding progression of the Cobb angle to 50 degrees or more. If treated with a TLSO brace, many idiopathic scoliosis patients would conceivably be subjected to years of brace wear and the cost and psychological factors inherent therein. Additional downsides of brace treatment include the potentially negative psychosocial impact of wearing an external sign of deformity during adolescence, a key period of emotional development. Prior research has identified negative psychosocial effects related to wearing a brace in children. Recent evidence has suggested that certain curve patterns will likely progress to 50 degrees or more, despite treatment with a TLSO brace. Sanders, et al. demonstrated a correlation of Cobb angle (greater than 35 degrees) and skeletal maturity (bone age 4 or less) to the risk of progression to 50 degrees or more, despite TLSO bracing. The evidence supports that the current practice of TLSO bracing is not an effective treatment to avoid progression to 50 degrees in these patients. It is on this population (thoracic Cobb angle greater than 35 degrees, bone age of 4 or less) that we intend to test the safety and efficacy of Anterior Vertebral Body Tethering to avoid curve progression to more than 50 degrees.