Rasch analysis of the Pediatric Evaluation of Disability Inventory–computer adaptive test (PEDI‐CAT) item bank for children and young adults with spinal muscular atrophy

Introduction: In this study we evaluated the suitability of a caregiver‐reported functional measure, the Pediatric Evaluation of Disability Inventory–Computer Adaptive Test (PEDI‐CAT), for children and young adults with spinal muscular atrophy (SMA). Methods: PEDI‐CAT Mobility and Daily Activities domain item banks were administered to 58 caregivers of children and young adults with SMA. Rasch analysis was used to evaluate test properties across SMA types. Results: Unidimensional content for each domain was confirmed. The PEDI‐CAT was most informative for type III SMA, with ability levels distributed close to 0.0 logits in both domains. It was less informative for types I and II SMA, especially for mobility skills. Item and person abilities were not distributed evenly across all types. Conclusions: The PEDI‐CAT may be used to measure functional performance in SMA, but additional items are needed to identify small changes in function and best represent the abilities of all types of SMA. Muscle Nerve 54 : 1097–1107, 2016     

Respiratory motor function in individuals with centronuclear myopathies

Introduction: Individuals with X‐linked myotubular myopathy (XLMTM) and other centronuclear myopathies (CNMs) frequently have profound respiratory insufficiency that requires support early in life. Still, few quantitative data exist to characterize respiratory motor function in CNM. Methods: We evaluated the reliance upon mechanical ventilation (MV), ventilatory kinematics, unassisted tidal volumes, and maximal respiratory pressures in 14 individuals with CNMs, including 10 boys with XLMTM. Results: Thirteen participants required full‐time, invasive MV. Maximal inspiratory pressures were higher in subjects who breathed unsupported at least 1 hour/day as compared with 24‐hour MV users [33.7 (11.9–42.3) vs. 8.4 (6.0–10.9) cm H₂O, P < 0.05]. Years of MV dependence correlated significantly with MEP (r = ?0.715, P < 0.01). Conclusions: Respiratory function in CNMs may be related to deconditioning from prolonged MV and/or differences in residual respiratory muscle strength. Results from this study may assist in evaluating severe respiratory insufficiency in neuromuscular clinical care and research. Muscle Nerve 53: 214–221, 2016     

Safety and feasibility of transcranial direct current stimulation in amyotrophic lateral sclerosis – a pilot study with a single subject experimental design

Introduction: Transcranial direct current stimulation (tDCS) has been explored as a neuromodulatory tool to prime motor function in several neurological disorders. Studies using tDCS in amyotrophic lateral sclerosis (ALS) are limited. We investigated the safety, feasibility and effects of long-term tDCS in an individual with ALS. Methods: A 36-year-old male diagnosed with clinically definite ALS received 12 sessions each of anodal, sham, and cathodal tDCS. Outcome measures included disease progression (revised ALS functional rating scale (ALSFRS-R)), clinical measures of endurance and mobility, and corticomotor excitability. Results: No adverse events or change in disease progression were noticed during the study. Small improvement in gait speed (15% increase) was noticed with anodal tDCS only. Conclusions: This case study demonstrates the safety and feasibility of long-term facilitatory and inhibitory tDCS on a single participant with ALS. This study serves as a guideline for implementing tDCS in future ALS trials.