A pilot study of scoliosis assessment using radiation free surface topography in children with GMFCS IV and V cerebral palsy

Abstract

Prevalence of scoliosis in cerebral palsy (CP) parallels the extent of neurological impairment and causes significant morbidity. Monitoring is important but requires regular radiological investigation. Surface topography provides a non-radiological approach to scoliosis monitoring. To evaluate validity, reproducibility and feasibility of Quantec(®) scans to monitor scoliosis in children with severe CP. Twenty non-ambulant children with CP, Gross Motor Function Classification System (GMFCS) grade IV/V had clinical, radiological and Quantec spinal assessment. The children were supported during scans using a seating system specifically designed for this study. Validity was assessed by comparing Quantec (Q) angle with gold standard (Cobb angle), reproducibility analysed using Bland-Altman plots and feasibility assessed using a questionnaire. Prevalence of scoliosis on radiological examination was 65%. Of these children, 85% had curves with Cobb angle less than 28°. Quantec scanning was feasible with appropriate postural support. Mean (and standard deviation) for differences between Cobb and Quantec (Q) angle were 0.02° (6.2°) and for Quantec inter-observer variability were 0.5° (5.8°). Quantec scanning was feasible, reproducible and had good validity when compared with Cobb angle in a supportive seating system. To consolidate these findings a further study needs to be undertaken with larger number of children with Cobb angles between 25° and 45°.