O2126: Growth-Friendly vs. Primary Fusion Surgery for Congenital Kyphosis: A Multicenter Analysis of Complications, Reoperations, and Patient Outcomes

Background: Surgical intervention for congenital kyphosis (CK) may be necessary to correct deformities, prevent progression, and minimize the impact on neurological and pulmonary function. Growth-friendly (GF) surgical approaches aim to preserve spinal growth but may result in increased complications and unplanned reoperations (UPRORs) compared to a primary fusion (PF). The purpose of this study is to compare complications, UPRORs, and patient-reported outcomes between GF and PF surgical treatments for CK.

Methods: An international, multicenter database for early-onset spinal deformity was queried to identify patients with CK who underwent operative management of the spinal deformity. Inclusion criteria were patients with a pre-intervention sagittal kyphosis greater than their major coronal deformity, with the major coronal deformity being < 35°, and were followed up for a minimum of 2 years. Patients were stratified based on the primary intervention into two cohorts: GF and PF. GF constructs included traditional growing rods, magnetically controlled growing rods, and vertical expandable prosthetic titanium ribs. Outcome data, including complications, UPRORs, and EOSQ-24 scores, were analyzed.

Results: 63 patients (35 PF; 28 GF) met inclusion criteria, with a mean follow-up of 3.0 years for PF and 4.2 years for GF. Preoperative and postoperative sagittal and coronal deformity were similar between groups. The change in sagittal deformity was similar, but the change in coronal deformity (PF, -6.2°; GF, -0.1°) was significantly greater for PF patients (p=0.0228). The change in T1-S1 length from preop to final increased 29.2 mm in the PF group (NS) and 42 mm in the GF group (p=0.0445), but between groups growth was similar (PF 9.9 vs. 11.6 mm/yr; NS). Complications occurred in 12 (34.3%) PF patients vs. 18 (64.3%) GF patients (p=0.0235), with PF patients experiencing a mean of 0.46 complications/patient compared to 1.3 for GF patients (p=0.0043). Complication types were similar between the groups. UPRORs were documented in 14.3% of PF and 35.7% of GF patients, with PF patients having statistically fewer (5 patients, 5 UPRORs, mean 8.4 months postop) compared to GF patients (10 patients, 15 UPRORs, mean 21.0 months postop) (p=0.0369). UPROR types were similar between the groups. Analysis of postoperative EOSQ-24 scores demonstrated PF patients had statistically higher scores for pulmonary function, energy level, child satisfaction, emotion, and parental impact domains vs. GF patients. All other domains were similar between groups.

Conclusion: In this study PF patients were older at surgery, had better coronal correction, and better EOSQ-24 scores. GF patients were younger, had similar sagittal deformity improvements, but had increased frequency of complications and UPRORs compared to fusions. Though GF aims to preserve spinal growth, there was no difference in postoperative T1-S1 growth rate per year across groups. Clinicians should consider these risk and benefits when discussing surgical treatments for CK to allow shared decision-making.