Effects of Different Stiffness Settings During Robotic Isokinetic Training in Children With SMA
Brief Summary
This randomized, within-participant, contralateral-limb-controlled clinical trial will compare individually optimized compliant and rigid stiffness settings of a portable isokinetic knee training robot in children with spinal muscular atrophy. At least 13 children aged 6 to 12 years will be enrolled. For each participant, one leg will be randomly assigned to the compliant setting and the contralateral leg to the rigid setting using sequentially numbered, opaque, sealed envelopes. Both legs will receive the same training volume, number of repetitions, and angular velocity for up to 8 weeks. The primary outcome is the between-setting difference in the change from baseline in peak isokinetic knee-extension torque. Secondary outcomes include knee-extension range of motion, quadriceps cross-sectional area on magnetic resonance imaging, femoral nerve conduction measures, and sit-to-stand performance. Knee pain, suprapatellar skin temperature, fatigue, and other adverse events will be monitored throughout the study.
Key Information
Inclusion Criteria:
- Age 6 to 12 years.
- Diagnosis of spinal muscular atrophy.
- Able to maintain an independent seated position.
- If receiving disease-modifying treatment, including nusinersen or risdiplam, the participant must have received a stable dose for at least 6 months before enrollment and must not change the treatment regimen during the study.
Exclusion Criteria:
- Any other major disease or medical condition that, in the investigator's judgment, would interfere with safe participation or interpretation of the study results.
- The legal guardian declines to provide written informed consent, or the participant is unable to complete the study procedures.
- Unable to undergo magnetic resonance imaging or electromyography and nerve conduction testing.
- Blood pressure above the 95th percentile for age, sex, and height, as assessed by a clinician.
- Lacks the cognitive capacity to understand or comply with the requirements of study participation.