Immediate and Sustained Effects of Intensive Equine-Assisted Physiotherapy Based on Neuroproprioceptive "Facilitation and Inhibition" on Psychomotor Development, Clinical Functions, Quality of Life, and Molecular Biological Indicators in Children With Spinal Muscular Atrophy: Protocol for a Crossover Randomized Controlled Trial.

Background: Spinal muscular atrophy (SMA) is a rare neuromuscular disease and the most common genetic cause of infant death. Although pharmacological treatment improves survival rates and functional capacity, physiotherapy remains a key component of care. A newly developed innovative equine-assisted physiotherapy method based on neuroproprioceptive "facilitation and inhibition" principles (NEUROEQUIP-SMA) is hypothesized to improve the quality and extent of motor development in children with SMA. Objective: The aim of this study is to assess the efficacy of NEUROEQUIP-SMA compared with standard individual outpatient physiotherapy based on the same neuroproprioceptive "facilitation and inhibition" principles (SMA-SOC-N) and to evaluate its effects on functional outcomes and quality of life (QoL). In addition, the response of molecular biomarkers to treatment will be assessed. Methods: In this crossover randomized controlled trial, 20 children with SMA types I-III, aged 2-9 years, will participate in two 6-day therapy programs (A and B) of equal duration (50 min per day) and separated by a 10-week washout period. Each child will be randomly assigned to receive the therapies in either the AB or BA sequence. Therapy A consists of a newly developed NEUROEQUIP-SMA (15 min twice daily), whereas therapy B involves SMA-SOC-N (30 min once daily). Both programs include therapeutic horse grooming (20 min a day). The Children's Hospital of Philadelphia Infant Test of Neuromuscular Disorders (CHOP INTEND) was selected as the primary outcome measure. Secondary outcomes included motor coordination assessed through 3D motion analysis, muscle fatigue, spirometry, and standardized clinical tests and rating scales, as well as monitoring of psychomotor development (via home-video analysis) and QoL (via questionnaires). Molecular biomarkers will be analyzed from blood samples. The immediate effect of the intervention will be evaluated for most outcomes, while psychomotor development and QoL will be monitored 28 days after therapy as longer-term outcomes. Treatment effect sizes will be reported alongside P values to illustrate the magnitude of changes in the outcomes. The study was approved by the Ethics Committee of the Third Faculty of Medicine, Charles University, under the number UK3LF/658559/12025. Results: The study is designed for 20 participants. Data collection will begin in February 2026 and will be completed in May 2026. Data analyses are planned for autumn 2026, and study results are expected to be available in 2027. A paired t test comparing the primary outcome (CHOP INTEND) between treatments NEUROEQUIP-SMA and SMA-SOC-N in 20 children will have 80% power to detect moderate-to-large effect size (Cohen d=0.66) at a 5% significance level. Conclusions: This trial will be the first study to evaluate the effects of NEUROEQUIP-SMA in children with SMA. If preliminary findings confirm a benefit, this physiotherapy approach may represent a promising adjunct to care for the generation of children undergoing gene therapy.