Traditional growing rod lengthening without intraoperative neuromonitoring: a 20-year institutional analysis demonstrating neurologic safety and cost savings

PURPOSE: To evaluate the neurologic safety and economic implications of performing traditional growing rod (TGR) lengthening procedures for early-onset scoliosis (EOS) without intraoperative neuromonitoring (IONM). Although IONM is widely adopted for deformity correction, its necessity during routine distraction lengthening procedures remains uncertain. METHODS: A retrospective cohort study was conducted of pediatric EOS patients (< 18 years) who underwent TGR lengthening procedures between 2000 and 2020 at a single tertiary children's hospital. Inclusion required documented neurologic assessments and radiographic follow-up within 6 months of the index surgery. Patients with alternative fixation strategies or incomplete records were excluded. Demographic, operative, and neurologic outcome data were collected from institutional registries and chart review. The use or omission of IONM was confirmed. Procedural cost estimates for IONM were obtained from institutional billing records using CPT-based rates. Descriptive statistics were calculated in SPSS v29. RESULTS: Fifty-nine patients (279 TGR lengthening procedures) met inclusion criteria. The mean age at index surgery was 6.6 ± 2.3 years. IONM was not used for any TGR lengthening procedures during this period. No immediate postoperative or delayed neurologic deficits were identified during the 20-year study period. The mean procedure duration was 45.2 ± 6.1 min. The estimated institutional cost of IONM per 45-min TGR lengthening was $6,500, representing an approximate cumulative savings of $1.81 million across all procedures. CONCLUSION: Over two decades, no neurologic complications occurred in TGR lengthening procedures performed without IONM, supporting the safety of omitting routine monitoring. Selective IONM use may yield substantial economic benefit without compromising patient outcomes.