Spinal Cord Stimulation for Poststroke Spasticity

Change in Mean Modified Ashworth Scale Score of the Primary Target Muscle Groups From Baseline to Week 6

The primary outcome is the change in the mean Modified Ashworth Scale (MAS) score of the Primary Target Muscle Groups from baseline to Week 6. The Primary Target Muscle Groups are selected from a upper or lower limb before treatment and must include at least two muscle groups. For the upper limb, eligible muscle groups include the shoulder adductors, shoulder internal rotators, elbow flexors, elbow extensors, forearm pronators, wrist flexors, and finger flexors. For the lower limb, eligible muscle groups include the hip flexors, hip adductors, hip internal rotators, knee flexors, knee extensors, and ankle plantar flexors. For analysis, the original MAS grades are converted to a 0-5 numerical scale, with grade 1+ converted to 2 and grades 2, 3, and 4 converted to 3, 4, and 5, respectively. The mean MAS score is calculated across the selected Primary Target Muscle Groups. Change is calculated as the Week 6 mean MAS score minus the baseline mean MAS score.

Change in Modified Ashworth Scale Scores of the Primary Target Muscle Groups From Baseline

Change in MAS of the primary target muscle groups from baseline to day 0, week 6, week 12, week 24, 1 year and 2 years after randomization

Proportion of Participants With an Improvement in Mean Modified Ashworth Scale Score of at Least 1 Point

A participant is defined as a responder when the mean MAS score of the Primary Target Muscle Groups decreases by at least 1 point compared with baseline. The outcome is reported as the proportion of responders at each assessment.

Change in Active and Passive Joint Range of Motion From Baseline

Active and passive range of motion are measured in degrees for movements corresponding to the assessed muscle groups. Upper-limb measurements include shoulder abduction, shoulder external rotation, elbow extension, elbow flexion, forearm supination, wrist extension, and metacarpophalangeal joint extension. Lower-limb measurements include hip extension, hip abduction, hip external rotation, knee extension, knee flexion, and ankle dorsiflexion. A greater range generally indicates better joint mobility.

Change in Fugl-Meyer Assessment Score From Baseline

The Fugl-Meyer Assessment (FMA) is used to assess motor and sensory function. The upper-limb motor score ranges from 0 to 66, and the lower-limb motor score ranges from 0 to 34. Light touch sensation is assessed at the upper arm, palm, thigh, and sole, with each site scored from 0 to 2, giving a total score of 0 to 8. Proprioception is assessed at the shoulder, elbow, wrist, thumb, hip, knee, ankle, and toe joints, with each site scored from 0 to 2, giving a total score of 0 to 16. Higher scores indicate better motor and sensory function.