Date of Award


Document Type

Open Access Thesis

Degree Name

Medical Doctor (MD)



First Advisor

Michael DiLuna

Second Advisor

Angeliki Louvi


Surgical Outcomes Following Posterior Spinal Fusion for Adolescent Idiopathic ScoliosisWyatt B. David and Michael DiLuna. Section of Pediatric Neurosurgery, Department of Neurosurgery, Yale University, School of Medicine, New Haven, CT. Hospital size has previously been shown to impact outcomes in adult spine surgery. However, there is a paucity of studies assessing the impact of hospital size on outcomes in adolescent spine surgery. Furthermore, gender-based differences have been suggested in disease progression and outcomes of adolescent idiopathic scoliosis (AIS), though only a few studies have investigated these disparities. The aim of this study was to determine the impact of hospital size and gender on length of hospital stay (LOS), complication rate, and costs of admission following posterior spinal fusion (PSF) for AIS. A retrospective cohort study was performed using the 2016-2019 National Inpatient Sample database. Patients 10-17 years old with a primary diagnosis of AIS undergoing elective thoracic PSF were identified using ICD-10-CM diagnostic and procedural coding. Patients were categorized by treating hospital size (Small, Medium, and Large), which incorporates hospital location and teaching status. Patients were also categorized on gender. Patient demographics, comorbidities, intraoperative procedures, postoperative adverse events (AE), length of stay (LOS), discharge disposition and hospital costs were assessed. Multivariate logistic regression analyses were used to identify the impact of gender and hospital size on extended LOS (defined as >75th percentile of LOS), total cost, and postoperative AEs. Of the 17,740 patients identified, 5,165 (29.1%) were in the Small cohort, 3,995 (22.5%) were in the Medium cohort, and 8,580 (48.4%) were in the Large cohort. Patients at Large hospitals generally had more comorbidities than patients at Small and Medium hospitals (p=0.006). Number of thoracic fusion levels were similar among the hospital size cohorts (p=0.648). A greater proportion of patients at Large hospitals experienced ≥1 adverse events (≥1 AE: Small: 23.3% vs. Medium: 32.1% vs. Large: 38%, p=0.009). LOS (p=0.956) and discharge disposition (p=0.380) were similar across all hospitals. Hospital costs were significantly lower at Large, and highest in Medium-size hospitals (Small: $53,381±26,900 vs. Medium: $65,445±29,170 vs. Large: $49,732±20,101, p


This is an Open Access Thesis.

Open Access

This Article is Open Access