Abstract
Distal adding-on (DAO) is a complication of spinal fusion characterized by postoperative deformity progression distal to the fusion construct. DAO after posterior spinal fusion for adolescent idiopathic scoliosis (AIS) is variably defined and inconsistently managed. This scoping review synthesizes evidence on DAO detection, management, and outcomes. A PRISMA-ScR–guided search identified relevant studies. Thirty-one studies (2,998 patients; median follow-up, 30 months) met inclusion criteria. Reported DAO incidence ranged from 3.5% to 62.5%, reflecting heterogeneity in definitions, patient factors, surgical constructs, and follow-up duration. Revision surgery was infrequent and typically delayed. When performed, it was most often prompted by progressive coronal decompensation rather than radiographic changes alone. Patient-reported outcomes were largely preserved; deterioration was observed primarily in younger adolescents and in those meeting stricter DAO criteria. Overall, DAO is most often a radiographic finding managed with surveillance. Significant symptoms develop in a minority of patients, and revision, typically distal extension of fusion, is reserved for progressive coronal imbalance or symptomatic deformity.
Recommended Citation
Hashem, Hussein; Hassan Abou Adma; Joseph Hayek; Ali Rezazadeh Shirazi; Karim Gaber; and Waleed Kishta. "Distal Adding-On as a Complication of Posterior Spinal Fusion in Adolescent Idiopathic Scoliosis: A Scoping Review of Contemporary Evidence." Western Journal of Orthopaedics 15, 1 (2026). https://digitalrepository.unm.edu/wjo/vol15/iss1/4