The Effects of Transcutaneous Spinal Cord Stimulation on Upper Extremity Function in Children and Young People With Hemiplegic Cerebral Palsy

Participants with stimulation-site skin reaction (Yes/No; photographic assessment)

时间窗: At the first session: Baseline (pre-tSCS) and immediately post-tSCS

Standardised photographs of the back will be obtained at each time point and reviewed by an independent clinician (not part of the study team). A skin reaction is defined as any visible erythema at/near the electrode site and will be recorded on a Yes/No erythema scale (0 = No erythema; 1 = Yes erythema). Results will be reported as the number and proportion of participants with ≥1 skin reaction during the session and by time point.

Heart Rate Category (beats per minute)

时间窗: [Time Frame: Baseline (pre-tSCS); During tSCS (10 minutes after start); Immediately post-tSCS (within 10 minutes after end) during a single session.

Heart rate will be measured immediately before and after tSCS using an OMRON M3 device. For each participant, a blinded independent clinician will classify the post-stimulation change relative to Baseline as one of three categories: Increased, Decreased, or No Apparent Change. Study results will be summarised as the number and proportion of participants in each category and described narratively.

Hand Strength Index (dynamometry)

时间窗: Session 1[first visit]: Pre (Baseline, before tSCS); Session 1 [first visit]: Post (immediately after tSCS, within 10 minutes); Session 2 [second visit]: Pre (Baseline, before tSCS); Session 2 [sv]: Post (immediately after tSCS, within 10 minutes)

Handgrip and pinch strength will be measured with handheld dynamometers (adjustable handle/pads; peak-hold). At each time point, participants perform 3 maximal attempts per measure; the average (mean) is calculated for handgrip and for pinch. Results will be summarised as mean (SD) by timepoint and change from pre to post within each session (Post - Pre). Component means (handgrip and pinch) will be presented descriptively as supportive information.

Jebsen-Taylor Hand Function Test total time (seconds)

时间窗: Session 1[first visit]: Pre (Baseline, before tSCS); Session 1 [first visit]: Post (immediately after tSCS, within 10 minutes); Session 2 [second visit]: Pre (Baseline, before tSCS); Session 2 [sv]: Post (immediately after tSCS, within 10 minutes)

Hand function will be assessed with the Jebsen-Taylor Hand Function Test (JTHFT). The protocol includes three subtests: (1) picking up small common objects; (2) stacking checkers; (3) lifting large light and large heavy cans (\~1 lb). Each subtest is timed to completion. Testing is administered with the less affected hand first, then the more affected hand; the primary outcome is the Total Score for the more affected hand. Results will be summarised as mean (SD) seconds by timepoint and change from pre to post within each session (Post - Pre). (Scores for the less affected hand may be presented descriptively as supportive data.)

Muscle Activity: Mean motor threshold to elicit ≥50 µV sEMG response (mA) - Delsys Trigno / Digitimer DS8R

时间窗: Session 1: Pre (Baseline, before tSCS); Session 1: Post (immediately after tSCS, within 10 minutes); Session 2: Pre (Baseline, before tSCS); Session 2: Post (immediately after tSCS, within 10 minutes).

Muscle activity will be assessed with surface EMG (Delsys Trigno). Sensors will be placed on the more affected arm over the abductor pollicis brevis, flexor carpi radialis, and extensor carpi radialis longus. Single spinal pulses (1 ms biphasic square-wave) will be delivered every \~5 s using a Digitimer DS8R. For each muscle at each time point, the motor threshold is defined as the lowest stimulation amplitude (mA) that produces an evoked sEMG response ≥50 µV. The participant-level outcome is the mean motor threshold (mA) across the three muscles. Results will be summarised as mean (SD) mA by timepoint and change from Baseline to Post.

Modified Ashworth Scale (0-4; higher = worse) - worst upper-limb muscle score (more affected limb)

时间窗: Session 1[first visit]: Pre (Baseline, before tSCS); Session 1 [first visit]: Post (immediately after tSCS, within 10 minutes); Session 2 [second visit]: Pre (Baseline, before tSCS); Session 2 [sv]: Post (immediately after tSCS, within 10 minutes)

Spasticity will be assessed with the Modified Ashworth Scale (MAS), scored 0, 1, 1+, 2, 3, 4 (0 = no increase in tone; 4 = rigid; higher scores indicate worse spasticity). The following muscles on the more affected upper limb will be tested in a fixed order: elbow flexors, wrist flexors, finger flexors. At each timepoint, the primary outcome is the worst (highest) MAS score across the tested muscles. Results will be summarised as median by timepoint and change from Pre to Post within each session (Post - Pre).

Systolic Blood Pressure Category (mmHg)

时间窗: Baseline (pre-tSCS); During tSCS (10 minutes after start); Immediately post-tSCS (within 10 minutes after end) during a single session.

Systolic blood pressure will be measured immediately before and after tSCS using an OMRON M3 device. For each participant, a blinded independent clinician will classify the post-stimulation change relative to Baseline as one of three categories: Increased, Decreased, or No Apparent Change. Study results will be summarised as the number and proportion of participants in each category and described narratively.

Diastolic Blood Pressure Category (mmHg)

时间窗: Baseline (pre-tSCS); During tSCS (10 minutes after start); Immediately post-tSCS (within 10 minutes after end) during a single session.

Diastolic blood pressure will be measured immediately before and after tSCS using an OMRON M3 device. For each participant, a blinded independent clinician will classify the post-stimulation change relative to Baseline as one of three categories: Increased, Decreased, or No Apparent Change. Study results will be summarised as the number and proportion of participants in each category and described narratively.