Comparison of Posterior Minimally Invasive Surgery and Vertebral Body Tethering in the Treatment of Adolescent Idiopathic Scoliosis: a Systematic Review and Meta-Analysis

Introduction: Adolescent idiopathic scoliosis (AIS) is a complex spinal deformity affecting the growing adolescent population, often requiring surgical intervention to prevent progression and achieve spinal alignment. Traditional approaches, such as posterior fusion, have long been the standard, but they often restrict spinal flexibility, impacting quality of life. Less invasive alternatives, including posterior minimally invasive scoliosis surgery (PMIS) and vertebral body tethering (VBT), have emerged due to their potential to correct spinal curvature while preserving motion segments. Our study compares the clinical effectiveness of PMIS and VBT for AIS patients.

Methods: A literature search was performed using PubMed, Embase, Web of Science, Scopus, and Cochrane Library. Inclusion criteria were skeletally immature AIS patients with Lenke type 1-5 curves and a minimum 2-year follow-up. 41 studies consisting of 815 patients treated with PMIS and 1,806 treated with VBT were analyzed. Preoperative values with a two-year follow-up for Cobb angle, thoracic kyphosis, and lumbar lordosis were analyzed and reported as standard mean difference (SMD), while complication and reoperation rates were presented as pooled rates. A random effects model was used to account for inter-study variability and heterogeneity.

Results: At 2-year follow-up, the PMIS group demonstrated a significantly greater reduction in Cobb angle compared to VBT (SMD: -5.60 vs. -2.13, p < 0.01). Thoracic kyphosis and lumbar lordosis corrections were comparable between PMIS and VBT groups (kyphosis, SMD: 0.10 vs. 0.15, p = 0.77; lordosis, SMD: -0.45 vs. -0.23, p = 0.33). The complication rate was higher in VBT than in PMIS (22% vs. 12%; 95% CI [13-31%] vs. [8-16%], p = 0.05), with pulmonary complications being the most common. Similarly, the reoperation rate was higher in VBT than PMIS (11% vs. 5%; 95% CI [8-15%] vs. [3-7%], p < 0.01).

Conclusion : Our findings reveal that PMIS achieves superior Cobb angle correction with lower complication and reoperation rates compared to VBT. The comparable kyphosis and lordosis outcomes between the two methods highlight their similar efficacy in sagittal plane correction. The lower complication rate associated with PMIS suggests it may be a more favorable option for skeletally immature patients, potentially offering improved long-term spinal health and reduced surgical risk.