The Researchers want to assess the short-term safety of Anterior Vertebral Body Tethering (AVBT) in skeletally immature subjects with moderate to severe scoliosis and compare them with a fusion cohort.

Inclusion Criteria:

1. Male & female, age 10 years to 16 years.
2. Scoliosis curve between 40-70 degrees.
3. At least 1 year of growth remaining measured by Sanders bone age 4 or less or Risser stage 2 or less.
4. Adolescent idiopathic scoliosis.
5. Lenke 1, 2, 3C, 5 (thoracic, thoracolumbar, or thoracic and lumbar).
6. Parents must be able to understand the study and sign the consent document. Assent will be obtained and documented as age appropriate.
7. Patients and parents must be able to comply with study procedures and visits, including 3-month, 1-year, and 2-year follow-up visits.

Exclusion Criteria:

1. Congenital, neuromuscular or syndromic scoliosis.
2. Underlying neuromuscular disease.
3. Pregnancy.
4. Nonflexible curves (bending films show residual curve greater than 40 degrees).
5. Prior surgery for scoliosis treatment.
6. Patients with active systemic infection.
7. Known, reported allergies to titanium, PET, or PCU. Known, reported substance abuse, including alcohol.