Comparison of efficacy of multi-modality spinal cord monitoring [SCM] (SSEP & MEP) in surgery of paediatric deformity using two classification systems I (traditional) vs. II (modified). SSEP SCM has low sensitivity in a normal spinal cord; this is only marginally improved with additional MEP monitoring. Traditional definitions of a ‘false’ positive' test ignores anaesthetic & surgical interventions following notification of altered SCM signals. Retrospective, paediatric cohort. 232 patients; mean age 14 years (26% males). 68% idiopathic scoliosis; 62% posterior surgery. Primary: Post-operative neurologic deficit. Secondary: significant (>50%↓ amplitude) SSEP or any MEP loss. PPV- Positive predictive value, NPV- Negative predictive value; LR+ve- Positive likelihood ratio, LR-ve Negative likelihood ratio; N/C – Not calculable Efficacy of SCM is determined by definitions of ‘false positive’. System II classification was more efficacious and reflects current surgical practice.
