Back pain in adolescent idiopathic scoliosis: frequency and risk factors.

Purpose: Although back pain is commonly reported in patients with adolescent idiopathic scoliosis (AIS), factors that influence the presence and severity of back pain in AIS, including curve-specific variables, have not been well studied. This study aims to describe the prevalence and severity of back pain in AIS patients and determine the extent to which patient characteristics, including curve-specific factors, are associated with a higher risk of back pain in AIS.

Methods: The study was a retrospective medical records review of adolescents (aged 10-17 years) diagnosed with AIS between 01/01/2018 and 12/31/2021 at an academic tertiary children's hospital. Patients with previous spine surgery were excluded. Variables collected included demographics (age, sex, race, insurance), Lenke classification, major coronal curve, back pain-related information, Risser stage, vitamin D levels, post-diagnosis brace utilization, physical therapy or chiropractic treatment, and surgery.

Results: A total of 891 AIS patients were included in the analysis. The sample was predominantly female (73.3%) and insured by Medicaid (57.8) with a mean age of 12.8 years. The mean major coronal curve was 26.3 degrees. Most patients had Lenke type 1 (47%) and type 5 (41%) curves. Nearly half of patients reported back pain (48.5%) with average pain severity in the low-to-moderate range (4.7) on FACES pain scale (0-10). Among those who reported back pain, 63.2% specified a location with the majority reporting pain in the lumbar region (56%) and, less commonly, in the thoracic (39%) and scapular (8%) regions. Lumbar pain was associated with significantly higher pain intensity (p = 0.033). Additionally, the location of pain reported was associated with location of major coronal curve (p < 0.0001). No association was observed between pain presence and vitamin D deficiency (p = 0.571, n = 175), major coronal curve magnitude (p = 0.999), Lenke curve type (p = 0.577), and sex (p = 0.069). Older patients, those insured by Medicaid, and those with higher Risser scores were more likely to report pain scores (p = 0.001 for all).

Conclusion: Nearly half (48%) of newly diagnosed AIS patients experience back pain which is higher than the prevalence of 33% seen in the general adolescent population. Pain was more prevalent among patients over the age of 13, with heavier body weight, and those insured by Medicaid. Pain was most commonly reported in the lumbar region, especially among patients with lumbar curves. This information can be helpful in counseling AIS patients, though further investigations are needed, especially to determine the underlying causes of back pain in AIS and to elucidate the discrepancy in pain between patients with Medicaid and commercial insurance.

Level of evidence: Prognostic Study Level II.