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Completed

NCT Number: NCT05467774

Operant H-reflex Down-conditioning of Rectus Femoris in Post-stroke Stiff Knee Gait

The investigators performed a feasibility trial of operant conditioning of spinal reflex excitability on five healthy individuals and two post-stroke individuals. The investigators found that operant conditioning of rectus femoris reflex excitability was feasible in all participants.

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Key information

Conditions

Training

Age range

18 year–75 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Early Phase 1

Primary location

University of Texas at Austin

Austin, Texas, 78712, United States

About this study

The investigators performed a cohort study on 7 individuals (5 healthy, 2 post-stroke) to examine the feasibility of operant down-conditioning of rectus femoris reflex excitability (i.e. H-reflex). Each individual performed 30 sessions, 6 baseline sessions with no operant conditioning (225 trials of surface electrical stimulation of the femoral nerve), followed by 24 training sessions (20 baseline trials followed by 225 trials with feedback of H-reflex magnitude). The investigators' main outcome measure was rectus femoris H-reflex magnitude. We also examined H-reflex magnitude of other quadriceps muscles.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Premorbidly independent
  • Mild to moderate impairment determined by standard practices per the physical therapist
  • Ability to stand for 10-minute intervals unassisted
  • Ability to walk for 10-minutes on a treadmill
  • Reduced knee flexion during phase and SKG as determined by a clinician
  • Hemiparesis
  • Ability to provide informed consent

Exclusion criteria

  • History of cerebellar stroke, multiple stroke
  • History of serious lower limb musculoskeletal injury
  • Functionally relevant osteoarthritis and weight-bearing restrictions
  • Have condition related to claustrophobia or other MRI contraindications
  • Functionally relevant cognitive impairment
  • Functionally relevant vision impairment
  • Took antispasmodic medication one day prior to the session
  • Had Botox injection one week prior to the session
  • Pregnant women

Treatment and study plan

Operant RF H-reflex conditioning

Behavioral

Operant down-conditioning of rectus femoris H-reflex

Primary outcomes

  1. Percentage Change From Baseline in RF H-reflex Magnitude

    Time frame: 3 months

    H-reflex magnitude of rectus femoris. Lower values are considered better. The H-reflex is the amplitude of the monosynaptic spinal reflex, elicitied by electrical stimulation of the femoral nerve, normalized by the preceding M-wave. The M-wave is the amplitude of the muscle activity response to surface electrical stimulation of the femoral nerve. All muscle activity measured at the individual's rectus femoris of the stimulated limb. A value of 100% would mean no change in reflex magnitude, whereas a change of -20%, for instance, would mean a 20% drop in reflex magnitude over the 3 month training period.

Secondary outcomes

  1. Percentage Change From Baseline in VM H-reflex Magnitude

    Time frame: 3 months

    H-reflex magnitude of vastus medialis. Lower values are considered better. The H-reflex is the amplitude of the monosynaptic spinal reflex, elicitied by electrical stimulation of the femoral nerve, normalized by the preceding M-wave. The M-wave is the amplitude of the muscle activity response to surface electrical stimulation of the femoral nerve. All muscle activity measured at the individual's vastus medialis of the stimulated limb. A value of 100% would mean no change in reflex magnitude, whereas a change of -20%, for instance, would mean a 20% drop in reflex magnitude over the 3 month training period.

Sponsors and collaborators

Lead sponsor

University of Texas at Austin

Other

Collaborators

  • Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Registry information

Important dates

Study start
2018
Primary completion
2020
Study completion
2020
First posted
Jul 21, 2022
Registry last updated
Jul 16, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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