Background: Thoracoplasty and insertion of vertical expandable prosthetic titanium rib (VEPTR) for thoracic and spine distraction has been found to be effective in the treatment of early-onset scoliosis (EOS) with ribs anomalies and congenital vertebral anomalies. The aim of this study was to evaluate the efficacy of VEPTR in preventing further progression of scoliosis without impeding spinal growth in children with progressive EOS without rib abnormalities.
Methods: This is a prospective, multicenter, observational cohort study. Erect radiographs were analyzed for coronal and sagittal curve and height measurements at preimplant, immediate postoperative, and at 2-year follow-up.
Results: Sixty-three patients met inclusion: 35 males and 28 females. Mean age at time of implantation was 6.1±2.4 years. Etiologies included congenital (n=6), neuromuscular (n=36), syndromic (n=4), and idiopathic (n=17). The mean follow-up was 2.2±0.4 years. Scoliosis (72±18 degrees) decreased after implant surgery (47±17 degrees) followed by slight increase at 2-year follow-up (57±18 degrees), P<0.0001. Kyphosis (48±22 degrees) also showed significant decrease after implantation (40±14 degrees), but increased after 2 years (48±16 degrees), P<0.0001. Coronal spine height measurements including T1-T12 (15.7±3 cm) and T1-S1 (25±6 cm) showed significant increases after implantation surgery (17.7±4 cm and 28.6±6 cm, respectively) and at 2 years (18.4±4 cm and 29.1±5 cm, respectively), P<0.0001. The increase in coronal spine height represented 144% of expected age-matched T1-T12 growth and 193% of expected age-matched T1-S1 growth. Similarly, sagittal spine length of T1-T12 and T1-S1 increased from 16.9±2.7 cm and 27.1±3.9 cm, respectively preoperatively to 19.7±3.5 cm and 31.9±5.1 cm, respectively at 2-year follow-up, P<0.0001. The instrumented spine segment continued growth from 25.8±5.2 cm after implantation to 27.4±5.3 cm at 2-year follow-up, P<0.0001. Thirty-one patients (49%) had at least 1 complication with total of 58 complications.
Conclusions: At 2-year follow-up, VEPTR was effective in treating EOS without rib abnormalities with 86% of patients having an improvement in scoliosis and 94% of patients having an increased spinal height as compared with preoperative values. This study proved that spine continues to grow after VEPTR instrumentation during the distraction phase. This amount of growth represents about 40% for T1-T12 and 31% for T1-S1 spine of the expected age-matched growth based on Dimeglio reference numbers. We find this growth important as it proves continuous spine growth with VEPTR treatment.
Level of evidence: Level II.