Spinal Muscular Atrophy (SMA) type I has classically presented extremely severe clinical features. New pharmacological treatments have led to a new phenotype of SMA. The aim of this study was to describe the current health and functional status of children with SMA. A cross-sectional study was conducted based on the STROBE guidelines. Patient questionnaires and standardized tools were used. A descriptive analysis was conducted establishing the proportions of subjects for each of the characteristics of interest. In total, 51 genetically confirmed SMA type I subjects were included. Fifty-seven percent received oral feeding, 33% received tube feeding and 10% combined both. Moreover, 21.6% had tracheostomies, and 9.8% needed more than 16 h/d ventilatory support. Regarding orthopedic status, 66.7% had scoliosis, and 68.6% had hip subluxation or dislocation. Up to 67% were able to sit independently, 23.5% walked with support and one child walked independently. Current SMA type I is a different entity from the classic phenotype but also from types II and III. In addition, no differences were found between SMA type I subgroups. These findings may enable the professionals involved in the care of these patients to improve their interventions in terms of prevention and rehabilitation measures for these children.

Background: Young children with spinal muscular atrophy type 1 (SMA1) have limited independent mobility and participation that may lead to cognitive development delays. Implementing early powered mobility in interventions may help them to learn self-initiated movement, play, and having fun to participate in natural settings. The aim of this study is to evaluate the effectiveness of an early power mobility intervention for increasing participation, functional ability, and quality of life in young children with SMA1. Methods: AMEsobreRuedas is a randomized waiting list controlled clinical trial. A sample of 24 children (10 months-5 years old, with SMA1) will be randomly allocated to two groups. The experimental group will perform a family-centered intervention with powered mobility for 16 weeks in their natural environment: a 12-week-structured program three times a week; and a 4-week follow-up with free use of the powered mobility device. The control group (waiting list) will keep their routine and will receive the same intervention after the experimental group. Five assessments will be carried out at baseline and weeks 4, 8, 12, and 16. Primary outcomes are participation (YC-PEM); functional ability (PEDI-CAT); and quality of life (PedsQL-Neuromuscular module). Results: It is expected that this study will provide further knowledge about the positive impact of powered mobility for the analyzed variables. Moreover, family engagement in the intervention and establishment of functional goals may help to add valuable information about real needs in future research. Conclusions: Early powered mobility could increase the opportunities for children with SMA1 to learn to move independently and participate in their natural environment.