Patient-perceived recovery after posterior spinal fusion: evaluating minimum clinically important difference (MCID) in adolescents with idiopathic scoliosis.

backgroundAdolescent idiopathic scoliosis (AIS) affects 1-3% of children in the United States, with approximately 38,000 patients undergoing posterior spinal fusion (PSF) annually. The relationship between preoperative patient-reported outcomes, postoperative recovery, and long-term clinical significance remains unclear. This study assesses longitudinal changes in Scoliosis Research Society-22r (SRS-22r) scores. It evaluates clinical significance using the Minimum Clinically Important Difference (MCID) in AIS patients undergoing PSF. STUDY

designRetrospective study using prospectively collected data.

methodsA retrospective study was conducted using prospectively collected data on AIS patients who underwent PSF at a single academic institution between 2012 and 2022. Patient-reported outcomes were assessed using the SRS-22r questionnaire at preoperative, 6-month, 1-year, and ≥ 2 years postoperative time points. MCID threshold achievements were determined using anchor-based criteria from Bago et al. The percentage of patients achieving MCID and predictors of MCID achievement were analyzed using logistic regression.

resultsA total of 161 patients (mean age 15.26 ± 2.15 years; 65.8% female) were included. At 1 year, MCID achievement ranged from 30.1% (Self-Image) to 43.4% (Mental Health). By ≥ 2 years, MCID rates declined in Pain (25.9%) and Self-Image (22.8%) but increased in Function/Activity (44.1%). Lower preoperative SRS-22r scores consistently predicted MCID achievement across all domains. A documented mental-health history reduced the likelihood of Pain MCID at 1 year, and larger postoperative Cobb angles independently decreased the odds of achieving Self-Image MCID at both follow-up points. Neighborhood opportunity (Child Opportunity Index) was not associated with outcomes. Sensitivity analyses demonstrated that complete-case ≥ 2 year MCID rates were consistently bounded by best- and worst-case values and closely approximated LOCF estimates, supporting robustness despite attrition.

conclusionMeaningful postoperative improvement after PSF varies substantially by SRS-22r domain. Pain and mental-health gains occurred early and stabilized, whereas function demonstrated ongoing recovery, and self-image improved rapidly and remained stable. MCID achievement was most likely in patients with greater preoperative symptom burden, while mental-health history and residual postoperative deformity diminished domain-specific improvements. The stability of MCID patterns across sensitivity analyses reinforces the reliability of long-term findings. These results highlight the importance of incorporating psychological assessment, expectation management, and attention to postoperative alignment into perioperative care for AIS patients.