Upper limb module in non-ambulant patients with spinal muscular atrophy: 12 month changes

Recent studies have suggested that in non-ambulant patients affected by spinal muscular atrophy the Upper Limb Module can increase the range of activities assessed by the Hammersmith Functional Motor Scale Expanded. The aim of this study was to establish 12-month changes in the Upper Limb Module in a cohort of non-ambulant spinal muscular atrophy patients and their correlation with changes on the Hammersmith Functional Motor Scale Expanded. The Upper Limb Module scores ranged between 0 and 17 (mean 10.23, SD 4.81) at baseline and between 1 and 17 at 12 months (mean 10.27, SD 4.74). The Hammersmith Functional Motor Scale Expanded scores ranged between 0 and 34 (mean 12.43, SD 9.13) at baseline and between 0 and 34 at 12 months (mean 12.08, SD 9.21). The correlation betweeen the two scales was 0.65 at baseline and 0.72 on the 12 month changes. Our results confirm that the Upper Limb Module can capture functional changes in non-ambulant spinal muscular atrophy patients not otherwise captured by the other scale and that the combination of the two measures allows to capture changes in different subgroups of patients in whom baseline scores and functional changes may be influenced by several variables such as age.