Staging growing rod insertion results in increased postoperative complications than the equivalent unstaged procedure

Anchor-related complications are the leading cause for unplanned surgery in early-onset scoliosis (EOS). One strategy to reduce unplanned surgery is staging implant insertion. This study compares the outcomes of staged versus unstaged growing rod (GR) insertion, focusing on complication rates.

This retrospective cohort study examined 48 EOS patients who received GR surgery at a single institution (Hospital for Sick Children, Toronto, Canada) between January 2006 and July 2023. Patients were grouped according to staged and unstaged GR insertion. Radiological measurements were obtained preoperatively, post-insertion, and one-year follow-up to determine radiological change between and within each group. Complications were recorded until posterior spinal fusion (PSF) or most recent follow-up if no PSF was performed, and compared between groups.

Overall, 24 patients received staged and 24 patients received unstaged dual GR insertion. The mean follow-up time for patients was 53.1 months (SD 33.1). Patients who underwent unstaged insertion had greater Cobb angle correction (46.6% (SD 15.9%) vs 31.5% (SD 13.3%), p < 0.001). There were no significant differences in kyphosis correction (p = 0.118) or thoracic height growth (p = 0.348) between groups. Staged patients experienced a higher complication rate compared to unstaged patients within the first year following insertion (38% vs 12%). Differences in proximal junctional kyphosis (PJK) development between staged (17%) and unstaged (29%) patients were not significant (p = 0.303). The mean insertion-associated length of stay was longer in staged patients (10.7 days (SD 4.2)) compared to unstaged patients (5.8 days (SD 4.0), p < 0.001).

Staged and unstaged GR insertion results in acceptable coronal correction and comparable radiological parameters. However, staged insertion may not be superior to unstaged insertion given the increased length of stay and rate of complications associated with the procedure.