Spinal Cord Injuries
Conditions
Keywords
Acute Intermittent Hypoxia, Transcranial Magnetic Stimulation
Brief summary
Our goal is to enhance repeated exposure to acute intermittent hypoxia (rAIH)/training-induced aftereffects on upper and lower limb function recovery in humans with chronic spinal cord injury (SCI).
Detailed description
The experiments in this study will test the following: Hypothesis 1.1(Experiment 1) that rAIH will enhance corticospinal excitability and upper and lower limb function in humans with incomplete SCI. Hypothesis 1.2 (Experiment 2) that enhancing the aftereffects of rAIH with exercise training will further enhance upper and lower limb motor function in humans with incomplete SCI. Measurements of corticospinal, cortical, and motoneuron excitability will be tested to further understand the mechanisms of this induced-plasticity. Persons with chronic (\>6 months) spinal cord injury between the levels of C2 and T2. SCI subjects must possess either the ability to produce a visible precision grip force with one hand, and/or the ability to perform some small wrist flexion and extension. Additionally, subject must possess the ability to perform a small visible contraction with dorsiflexion and hip flexor muscles. Controls must be right handed due to potential differences in the organization of the brain in right handed and left handed individuals.
Interventions
OTHERRepeated exposure to acute Intermittent Hypoxia (rAIH)
Participants will be fitted with a mask that will be placed over mouth and nose. Tubing will be attached to the front of the mask. The session will last approximately 30-45 minutes with 60-90 seconds of lower oxygen (tubing attached, 9-10% oxygen level), alternating with 60-90 sec of normal room air (no tubing attached).
OTHERNormal Room Air
Participants will be fitted with a mask that will be placed over mouth and nose. Tubing will be attached to the front of the mask. The session will last approximately 30-45 minutes with 60-90 seconds of normal room air (with tubing attached to the mask) and 60-90 sec of normal room air (without the tubing attached to the mask).
OTHERUpper-limb Training by Research Staff
Training sessions will last for approximately 30 minutes, with additional time for set up. During these sessions, participants will be asked to complete a variety of tasks related to general arm/hand movement, gross grasping, fine grasping, and hand cycle using an arm ergometer. The number of repetitions will be monitored and adjust the difficulty to ensure appropriate task difficulty.
OTHERLower-limb Training by Research Staff
Training sessions will last for approximately 30 minutes, with additional time for set up. During these sessions, participants will be asked to complete a variety of tasks related to general leg/foot movement, over-ground walking, treadmill walking, stair climbing training, leg cycling, standing frame, and NuStep. The number of repetitions will be monitored and adjust the difficulty to ensure appropriate task difficulty.
Sponsors
U.S. Department of Education
Shirley Ryan AbilityLab
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Caregiver)
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
Yes
Inclusion criteria
for SCI: 1. Males and females between 18-85 years 2. Chronic SCI (≥ 6 months post injury) 3. SCI at or above L2 4. ASIA A, B, C, or D, complete or incomplete 5. Possess the following: The ability to produce a visible precision grip force with one hand, and/or the ability to perform some small wrist flexion and extension. The ability to perform a small visible contraction with dorsiflexion and hip flexor muscles. Inclusion criteria for controls: 1. Males and females between 18-85 years 2. Right-handed (Only right-handed individuals will be accepted into this group because of the potential differences in the organization of the brain in right handed and left handed individuals)
Exclusion criteria
for SCI and for controls: 1. Uncontrolled medical problems including pulmonary, cardiovascular or orthopedic disease 2. Any debilitating disease prior to the SCI that caused exercise intolerance 3. Premorbid, ongoing major depression or psychosis, altered cognitive status 4. History of head injury or stroke 5. Metal plate in skull 6. History of seizures 7. Receiving drugs acting primarily on the central nervous system, which lower the seizure threshold such as antipsychotic drugs (chlorpromazine, clozapine) or tricyclic antidepressant 8. Pregnant females 9. Ongoing cord compression or a syrinx in the spinal cord or a spinal cord disease as spinal stenosis, spina bifida or herniated cervical disk. AIH
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Upper limb functional measurement | 45 minutes to 1 hour | The Graded Redefined Assessment of Strength, Sensibility and Prehension (GRASSP) will be used to assess sensation, strength, and prehension. |
| Lower limb functional measurement | 5-10 minutes | 10-meter walk test will be used to assess walking speed |
| MEP/CMEP recruitment curves using TMS | 30 minutes to 1 hour | Ten Transcranial magnetic stimuli (TMS) will be delivered to plot the mean peak-to-peak amplitude of the motor and cervicomedullary evoked potentials (MEPs and CMEPs, respectively) from the non-rectified response against the TMS intensity in each subject (MEP/CMEP recruitment curves). |
| EMG and force voluntary output | 30 minutes to 1 hour | EMG surface electrodes will be placed over target muscles (deltoid, biceps brachii, first dorsal interosseous, abductor pollicis brevis, quadriceps femoris, tibialis anterior and/or soleus) to measure maximum voluntary contraction (MVC) |
Countries
United States
Contacts
Primary ContactMonica Perez, PhD
Outcome results
None listed