Longitudinal Analysis Of Mobile Smartphone Application For The Assessment Of Facioscapulohumeral Muscular Dystrophy (FSHD) Gait

Abstract

Facioscapulohumeral muscular dystrophy (FSHD) can be categorized as having a loss of muscular function in the torso, pelvic girdle, and legs. FSHD patient’s gait may decline over time, which could be used as a marker of disease progression. If so, this may be beneficial for potential clinical trials. PURPOSE: Evaluate gait velocity and cadence across three gait tasks using a novel smartphone application among individuals with FSHD over 6 months. METHODS: 2 (male = 1, female = 1; avg. age = 65 years) genetically confirmed FSHD1 patients completed three gait trials that required them to walk on a level surface at home 5 out of 7 days a week at two time points, 6 months apart. Patients used a custom smartphone application (FSHD Gait), installed on a smartphone (LG KG40) and secured on the lower back using a running belt, while walking. FSHD Gait application was used to take pictures of their shoes and walking environment. The first task (T1) involved walking 10 meters 12 times once each day. The second task (T2) was to walk 10 meters 6 times, with 6 trials being performed in the morning and 6 in the afternoon with a minimum of 4 hours between sessions. In the final week (T3), participants were instructed to walk for 6 minutes without any breaks. One-way ANOVAs compared the two time points while controlling for shoe type and walking surface. RESULTS: Over the course of 6 months, neither participant expressed a significant decline in gait velocity. There was no difference in gait velocity between time point one and two for T1 (PRE = 0.93 ± 0.24 m/s, POST = 0.85 ± .04 m/s; Cohen’s d = 0.27; p = 0.75), T2 (PRE = 0.93 ± 0.15 m/s, POST = 0.88 ± 0.07 m/s; Cohen’s d = 0.50, p = 0.54) or T3 (PRE = 0.94 ± 0.21 m/s, POST = 1.00 ± .09 m/s; Cohen’s d = 0.47; p = 0.63). Similarly, over the course of 6 months, neither participant expressed decline in cadence between time point one and two for T1 (PRE = 94.07 ± 4.78 steps/min, POST = 99.66 ± 6.44 steps/min; Cohen’s d = 3.36; p = 0.13), T2 (PRE = 103.71 ± 5.17 steps/min, POST = 0.85 ± 0.04 steps/min; Cohen’s d = 0.44; 0.64) or T3 (PRE = 98.74 ± .25 steps/min, POST = 86.88 ± 11.30 steps/min; Cohen’s d = 1.03; p = 0.35). CONCLUSION: FSHD Gait application can successfully collect and analyze gait for FSHD patient assessments over a 6-month period. While cadence nor velocity significantly changed, overall both metrics declined in both participants during T1 and T2.