Analyzing Factors Associated with Postoperative Shoulder Imbalance in Lenke2 Adolescent Idiopathic Scoliosis (Retrospective Cohort Study)

World Neurosurg. 2024 Oct:190:e8-e16. doi: 10.1016/j.wneu.2024.06.055. Epub 2024 Jun 18.

Abstract

Objective: To assess the incidence of postoperative shoulder imbalance (PSI) following posterior spinal fusion surgeries in adolescent idiopathic scoliosis (AIS) with Lenke2 and calculate the risk factors for PSI.

Methods: Sixty patients who underwent surgery for Lenke2 AIS with more than 2-year follow-up were selected. Radiographic parameters were measured before and after surgery, and at the latest follow-up. The patients were divided into PSI and non-PSI groups, with PSI defined as a radiographic shoulder height >15 mm on postoperative radiography. The factors were compared between the PSI and non-PSI groups using the Mann-Whitney U test or chi-squared test. Finally, explanatory variables were chosen for multivariate analysis based on previous studies.

Results: The PSI group comprised 17 patients. Most PSI cases spontaneously improved, and four patients (6.7%) showed PSI at the final follow-up. Univariate analysis indicated significant differences between postoperative T1 tilt (9.00 ± 5.17 vs. 5.67 ± 4.02, P = 0.029), UIV tilt (1.94 ± 4.49 vs. -1.00 ± 5.04, P = 0.039), and ΔT1 tilt (4.82 ± 3.99 vs. 2.12 ± 3.77, P = 0.026). Multivariate logistic regression analysis indicated that ΔT1 tilt had a significant positive relationship with PSI occurrence (coefficient = 0.2541, 95% confidence interval [CI]: 0.023 to 0.485, P = 0.0310). This study found no significant differences in the SRS-22 scores at the final follow-up.

Conclusions: The incidence of PSI for Lenke2 AIS was 28.3% at 1 week postoperatively and 6.7% at the final follow-up. ΔT1 tilt was a risk factor for PSI. Adjustment of the T1 tilt during surgery was considered useful for the prevention of PSI.

Keywords: Associating factor analysis; Lenke type 2; Postoperative shoulder imbalance.

MeSH terms

  • Adolescent
  • Child
  • Cohort Studies
  • Female
  • Follow-Up Studies
  • Humans
  • Male
  • Postoperative Complications* / diagnostic imaging
  • Postoperative Complications* / epidemiology
  • Postoperative Complications* / etiology
  • Postural Balance / physiology
  • Retrospective Studies
  • Risk Factors
  • Scoliosis* / diagnostic imaging
  • Scoliosis* / surgery
  • Shoulder* / diagnostic imaging
  • Shoulder* / surgery
  • Spinal Fusion* / adverse effects
  • Spinal Fusion* / methods