Thoracoscopic Vertebral Body Tethering for Adolescent Idiopathic Scoliosis: A Minimum of 2 Years' Results of 21 Patients

Background: Anterior vertebral body tethering (VBT) is a growth modulating and fusionless treatment option that is considered as a new promising method for the management of adolescent idiopathic scoliosis (AIS). This prospective cohort study aimed to present the minimum 2-year results of anterior VBT applied to 21 skeletally immature patients with AIS. Methods: Twenty-one skeletally immature patients with a diagnosis of AIS were included. A decision to proceed with surgery was established after the detection of curve progression despite the brace (>40 degrees) with a minimum curve flexibility of 30%. Results: Patients had an average age of 11.1 and an average follow-up period of 27.4 months. All patients underwent thoracoscopic placement of thoracic screws, from the convex side of curves. An average of 7.1 levels of tethering was undertaken. Average preoperative major thoracic curve magnitudes improved from 48.2 to 16 degrees on the first erect postoperative x-ray, and to 10 degrees at the last follow-up (P<0.001). Immediate postoperatively, 1 case with chylothorax was detected and treated conservatively, and another case with tether breakage was detected at the third postoperative year and replaced thoracoscopically. No other major complication was acquired. Conclusions: Anterior VBT as a growth modulating treatment option by allowing the correction of the scoliotic deformity and preserving coronal balance was detected to be a safe and effective option for the surgical treatment of AIS in skeletally immature patients, if applied under strict inclusion criteria. VBT by allowing preservation of spinal segmental motion is yielding promising radiographic results without causing any major complications.