Inclusion Criteria:

• * Subjects whose parent(s) or guardian(s) has/have signed and dated the informed consent form (ICF) for the subject to participate in the study
• * Patients with a diagnosis of juvenile idiopathic scoliosis (JIS) or adolescent idiopathic scoliosis (AIS) who will have posterior spinal fusion surgery
• * Male or female patients 11 to less than 18 years of age on the day of surgery.
• * American Society of Anesthesiologists (ASA) Class 1-2.
• * Able to adhere to the study visit schedule and complete all study assessments.

Exclusion Criteria:

• * Body mass index ≥35 at the time of screening
• * Contraindication to regional anesthesia (e.g., abnormal coagulation, infection at site)
• * Current opioid use at the time of screening
• * Current diagnosis of chronic pain
• * Allergy, hypersensitivity, intolerance, or contraindication to any of the study medications
• * Administration of liposomal bupivacaine (LB, Exparel)
• * Subject/parent/guardian primary language other than English or Spanish
• * Inability of patient to verbally express symptoms such as pain and side effects (as in moderate to severe developmental delay)
• * A prolonged QTc on preoperative EKG (QTc longer than 450 milliseconds)
• * History of Torsades de Pointes
• * Renal or hepatic impairment
• * Diagnosed active seizure disorder
• * Any other condition that causes patient to be ineligible for surgery, i.e. pregnancy.