Radiographic Coronal Imbalance and Shoulder Asymmetry Continue to Improve Between 2 and 5 Years Following Surgery of Adolescent Idiopathic Scoliosis

Background: Managing patients with coronal imbalance (CI) and shoulder height asymmetry following scoliosis surgery can be challenging. Little is known about the course of findings over time and whether they improve or persist. The aim was to report the rate of suboptimal radiographic CI or shoulder asymmetry (SA) at 5 years in patients who were already reported to have CI or SA 2 years after surgery for adolescent idiopathic scoliosis (AIS). Methods: An AIS database was reviewed for patients with both 2- and 5-year follow-up after surgery. From this cohort, patients with CI>2 cm or SA>2 cm at their 2-year follow-up were identified and reevaluated, using the same parameters, at 5-year follow-up. Results: Of 916 patients, 157 (17%) patients had CI and 69 (8%) patients had SA at 2-year follow-up. At 5 years this improved to 53 (6%) and 11 patients (1%), respectively. Conclusions: Having coronal or shoulder imbalance 2 years after surgery for AIS does not guarantee continued imbalance 5 years after surgery. Most patients demonstrate some improvement in these measures of clinical deformity. Anticipating the potential course following a postoperative coronal balance and shoulder height differences can help surgeons manage and counsel their patients appropriately.