223. A single surgeon's experience of thoracoscopic VBT: 5- to 8-year follow-up results

Abstract

<h3>BACKGROUND CONTEXT</h3> There is a paucity of information on mid- to long-term clinical and radiographic outcomes of VBT surgery. <h3>PURPOSE</h3> The aim of the study was to report mid-term outcomes of thoracoscopic thoracic-only anterior VBT surgery. <h3>STUDY DESIGN/SETTING</h3> Retrospective analysis of prospectively collected data. <h3>PATIENT SAMPLE</h3> Twenty-three (22F, 1M) consecutive adolescent idiopathic scoliosis (AIS) patients with a mean age of12.1±1.5years at surgery, and a mean follow-up of 63 (60-92) months who underwent thoracoscopic VBT surgery between 2014 to 2017 were included. <h3>OUTCOME MEASURES</h3> Coronal curve measurements were compared at each time point. Clinical outcome was assessed by SRS-22r. <h3>METHODS</h3> Data were collected preoperatively, at 6-week, 1-, 2- and 5-year follow-up. Demographic, perioperative, clinical, radiographic data and complications were analyzed. Curve sizes at each follow-up were compared using repeated measures ANOVA. Clinical outcome was assessed by using SRS-22r questionnaire. <h3>RESULTS</h3> Ninety-six percent of the patients displayed a Lenke 1 (11A, 2Ar, 9B and 1C) curve pattern while 4% had a Lenke 2 pattern. Preoperatively, 14 (64%) patients were premenarchal (median Sanders: 3 [1-7], median Risser: 0 [0-5]). A median of 7 (7-9) levels were tethered. Mean surgical time was 245±75 (123-360) minutes. Patients grew 7 cm on average; height measurements showing significant increase at each follow-up timepoint (p < 0.001). All patients reached skeletal maturity at final follow-up. Upper thoracic (UT), main thoracic (MT) and thoracolumbar/lumbar (TLL) curves showed significant decrease in each follow-up timepoint until 2-year follow-up. Thereafter, curve magnitudes were either stable or deteriorated slightly. No significant changes were noted in kyphosis and lordosis (p < 0.05). Pulmonary (ie, atelectasis, effusion), mechanical (ie, broken tether, implant-related) and curve behavior (ie, overcorrection, distal adding-on) complications rates were 13%, 22% and 35%, respectively. Three (13.0%) of patients had undergone a total of 4 reoperations, in which 2 (8.7%) had a tether release, and 2 (8.7%) patients were converted to fusion. At final follow-up, 91% patients had a ≤30° residual curve. SRS-22 mental health, self-image and subtotal scores increased significantly. <h3>CONCLUSIONS</h3> This study reports a single European center experience on 23 consecutive patients with 5-year follow-up who had undergone thoracic-only VBT surgery. Surgical correction was followed by growth-dependent correction attained during follow-up. Spontaneous correction in the nonoperated upper thoracic and thoracolumbar levels were also noted. Thoracoscopic VBT surgery prevented fusion following 5-years after surgery in 91% of the patients. A total of 90% of patients that were not converted to fusion had good radiographic and clinical outcomes at latest follow-up; however, it is not without complications. Some complications may be avoided with a better understanding of the growth modulation and advancement of technical skills and technology. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.