Study Design: Retrospective, multicenter analysis of electronic medical record (EMR) data from a national pediatric orthopedic health care system. Objective: To determine whether the lowest instrumented vertebra is associated with changes in PROMIS scores in patients with adolescent idiopathic scoliosis and to evaluate for correlations with SRS-22. Summary of Background Data: Appropriate selection of the lowest instrumented vertebra (LIV) is crucial to ensure positive outcomes after surgical management of patients with adolescent idiopathic scoliosis (AIS). Preservation of motion segments is believed to be beneficial for preserving motion and preventing degeneration of the unfused lumbar spine, leading to a positive impact on a patient’s quality of life. Prior studies have shown moderate correlations between the Spine Research Society score (SRS-22) as well as Oswestry Disability Index (ODI) score and the lowest instrumented vertebra; however, there is limited data using the Patient-Reported Outcomes Measurement Information System (PROMIS) scores as related to LIV. Methods: A set of patients who had undergone primary posterior spinal fusion for AIS from January 2011 to January 2023 with PROMIS or SRS-22 scores documented pre-surgery and post-surgery was queried. PROMIS survey scores, SRS-22 survey scores, clinical dates, sex, and LIV were collected from the EMR. Results: The study cohort consisted of 348 patients with PROMIS data and 341 patients with SRS-22 data. Neither the PROMIS scores nor SRS scores met the threshold for clinically significant differences with LIV level. Conclusions: In this study, LIV for AIS was not correlated with PROMIS or SRS-22 scores at 2 years. Longer term follow-up will be necessary to differentiate whether patients’ outcomes will be affected by LIV selection. Level of Evidence: Level III.
Sborov et al. (2025) studied this question.