Daily Quantity and Kinematic Characteristics of Leg Movement in a Child With SMA (2 Copies SMN2).

Purpose: This case report describes daily leg movement quantity and kinematic characteristics of a child with spinal muscular atrophy (SMA) with 2 copies of SMN2, who was symptomatic at the time of treatment with disease-modifying therapies.

Key Points: Compared with infants with typical development, this child had differing values for leg movement quantity, duration, average acceleration, and peak acceleration measured across full days in the natural environment by wearable sensors. In addition, movement quantity and clinician-rated outcomes increased with age.