Children with spinal muscular atrophy treated with disease-modifying therapies, do they attain neutral vertical head and trunk control?

AimTo investigate whether children with various spinal muscular atrophy (SMA) subtypes treated with disease-modifying therapies (DMT) obtain neutral vertical (NV) head and trunk control, and how this relates to motor function. MethodIn this observational cross-sectional study, a convenience sample of 21 children diagnosed with SMA (6y1m (4y), 10 female) was tested with Segmental Assessment of Trunk Control (SATCo) and functional assessments. A linear mixed-effects model (LME) was used for statistical analysis. ResultsSATCo scores were measurably different between condition (types of SMA), F=4.96, p<.05, and control type (static, active, and reactive control), F=6.40, p<.05. The interaction condition*control type was also significant, F=3.14, p<.05. No child with SMA1 demonstrated NV head control and there was no relationship between SATCo scores and motor function. Four children with SMA2 and SMA3 demonstrated NV head static control, and one demonstrated NV mid-thoracic static control. InterpretationThe results indicate that children with SMA treated with DMTs acquire very little or no unsupported NV head/trunk control. SATCo was shown to be sensitive to differences in trunk control in different types of SMA revealing potential as an outcome measure for therapeutic interventions or treatment effectiveness. Further studies are needed to clarify this potential. What this paper addsO_LIChildren with SMA1 treated with DMTs do not attain upright head control C_LIO_LISome children with SMA2/SMA3 treated with DMTs attain upright head/trunk control C_LIO_LIDifferences in caudal extent of head/trunk control were found between SMA types C_LIO_LISATCo is more efficient in identifying upright head/trunk control than functional tests C_LIO_LIPostural control assessment using SATCo has the potential to track treatment outcomes C_LI