Scoliosis is a condition in which the spine is deformed by a curvature in the coronal plane. It is generally associated with a twisting (axial plane) deformity as well. It can have a variety of underlying etiologies and the etiology is used to classify the types of scoliosis. Idiopathic scoliosis is sub-classified in two ways: by age of onset and by magnitude of deformity. 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 scoliosis 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 feasibility of Anterior Vertebral Body Tethering to avoid curve progression to 50 degrees.~The study intervention is surgical orthopedic implantation of the Anterior Vertebral Tether Device, by way of thoracoscopic surgery under general anesthesia. The primary outcome measures include assessments of safety of the insertion procedure and of the device, as well as the secondary measure of feasibility by determining the ability to successfully implant the investigational device.
This study will determine whether vertebral body tethering is a safe and feasible method of treatment for pediatric idiopathic scoliosis.