Failure to replace removed growth friendly implants results in deteriorating radiographic outcomes.

Introduction: Management of early onset scoliosis (EOS) patients can require growth-friendly surgery to manage spinal deformity in children too immature for a definitive fusion. There is limited literature on outcomes for patients with failed growing constructs requiring removal of implants (ROI).

Methods: We studied EOS patients from an international registry undergoing removal of growth-friendly implants, comparing early re-implantation (within 12 months of ROI) to observation-only. We examined demographic data and radiographic measurements with a significance level of p < 0.05.

Results: Sixty-four patients met the inclusion criteria for radiographic analysis: 53 had early re-implantation and 11 were observed. There were no significant differences between the groups in age at index, ROI, or etiology. Pre-ROI, observation and re-implantation groups had similar coronal Cobb angles (55° vs 47°, p = 0.35) and similar time from index procedure to ROI. However, at two years post-ROI, the observation group had a larger coronal Cobb angle than the re-implantation (81° vs 53°, p = 0.003). In the re-implantation group, 16 (30%) patients progressed ≥ 5° vs 7 (64%) in the observation group (p = 0.04). The re-implantation group had a smaller difference in major Cobb angle between post-ROI and two years post-ROI (-2° vs 12°, p = 0.01). The re-implantation group had no significant progression in the major Cobb angle at two years post-ROI compared to immediate post-ROI (55° vs 53°, p = 0.36), while the observation group increased by about 13° (68° vs 81°, p = 0.03), resulting in a total increase of more than 25° from pre-ROI.

Conclusion: Our interim data strongly suggest that promptly replacing removed implants stabilizes curves in this population of EOS patients. Timely re-implantation should be a priority, when possible, to enhance outcomes, despite technical challenges for some patients.