O1053: Unplanned Staged Posterior Spinal Fusion in Neuromuscular Scoliosis: Is It Safe?

Background: Patients with neuromuscular scoliosis (NMS) are often medically complex with severe curves. Despite their complexity, we often attempt one-stage procedures to address their spinal deformity. However, staged PSF can be a necessary intra-operative decision when there are patient safety concerns. We hypothesize that despite the need for an unplanned two-stage procedure, patients will have a similar outcome.

Methods: Retrospective review of consecutive NMS patients undergoing posterior spinal fusion (PSF) at a tertiary pediatric hospital between 2004 and 2019. Patients with history of prior spinal surgery, absent baseline neuromonitoring signals and planned two stage procedures were excluded. Postoperative complications were collected. Two groups were established, a one-stage PSF group and an unplanned two-stage PSF group.

Results: 12 (4.9%) of 243 NMS patients had an unplanned two-stage PSF. Reasons for aborting surgery prior to completion were change in intra-operative neuromonitoring signals (n=5), significant blood loss (n=6) and anaphylaxis (n=1). 231 (95.1%) of patients underwent a one-stage procedure.

The average pre-operative Cobb was larger in the two-stage group 97.1 ± 26.5° vs 79.0 ± 22.9° for the one-stage group (p=0.0017). There was a trend toward greater percent Cobb correction in the one-stage group, 81.9% vs 63.4% for the two-stage group, though this was not significant (p=0.2290).

There was a similar complication rate in both groups (p=0.7099), with 3 patients in the two-stage group (25%) having complications compared to 41 (17.7%) in the one-stage group. Complications included infection, wound dehiscence, pneumonia, urinary tract infection (UTI) and instrumentation revision. Complications are listed in Table 1.

Conclusion: Overall rate of unplanned staged PSF in NMS was low at 4.9%. There was no significant increase in complications with an unplanned two-staged PSF compared to one-stage PSF in NMS. This study provides reassurance that a two-staged PSF can be implemented without increasing complications when there are intraoperative concerns about patient safety.