The Risks and Benefits of Definitive Surgery in the Graduation of Idiopathic Early-Onset Scoliosis (I-EOS) Patients Whose Deformities Were Managed With Growing Rods: A Comparison With Matched Adolescent Idiopathic Scoliosis (AIS) Patients.

Abstract

Background: Growing rod treatment (GR) is one of the most popular methods for idiopathic EOS and is usually followed by posterior instrumented spinal fusion (PISF), which is also called graduation. Graduation surgery is technically demanding and complicated, leading to a tendency to avoid definitive fusion when there is an adequate improvement in scoliosis angle, no implant failure, and no need to change the instrumentation level. The aim of the present study was to compare the risks and benefits of PISF between patients with adolescent idiopathic scoliosis (AIS) treated with standard PISF against those with idiopathic EOS treated with GR and graduated with PISF.

Methods: The study included patients with I-EOS who were treated with dual GR and PISF, and those with AIS who underwent standard PISF with AIS during the study period. The AIS and EOS groups were matched in terms of scoliosis curve magnitude, T2-T12 kyphosis, L1-S1 lordosis, sex, and age variables by propensity score matching.

Results: Seven hundred seventy-six patients (24 EOS and 752 AIS) were included in the study. Seventy-two AIS patients were matched against 24 EOS patients. Statistically significant differences were found between the groups in terms of scoliosis correction percentage, surgical time, transfusion need, and number of instrumented segments. However, the percentage of T1-T12 length increase, percentage of T1-S1 length increase, instrumented spinal segment length increase, and the estimated blood loss were similar between the groups.

Conclusion: Although the EOS group had longer surgical time (30 min longer), more bleeding (75 cc more), and less correction of the coronal deformity, trunk height gained by definitive surgery was the same as that in the AIS group. There was a difference in favor of AIS between the groups in terms of coronal deformity correction rates, but the final deformity size in the EOS patients was clinically insignificant (22±13 degrees). Definitive fusion in EOS with idiopathic etiology does not carry an excessive risk for complications, and the gains obtained by the patients after surgery are comparable to AIS patients who underwent PISF surgery.

Level of evidence: Level III.