Overview
This study aims to observe the effects of administration of a breathing intervention (Acute Intermittent Hypoxia (AIH)) on spasticity (tightness) in individuals with incomplete Spinal Cord Injury. It is hypothesized that hypoxia will decrease the reflex threshold of the biceps brachii, indicating an increase in spasticity following the AIH.
Description
In the case of incomplete traumatic spinal cord injury, it is know now that muscular strength improves quickly after AIH administration, and this Increase in voluntary strength lasts from three to six hours. The Increase in strength, coupled with demonstrated improvements in spinal cord neural plasticity, makes AIH administration a potentially valuable new therapeutic intervention. AIH initially acts by releasing serotonin in the central nervous system, enhancing persistent sodium uptake (via the motor neuron soma) and activating voltage-gated calcium channels in motor neuron dendrites. There are also other effects of serotonin on motor neuron excitable channels. One potential complication of hypoxia is linked to the changes in motor neuron excitability in humans with SCI.
These issues may be relevant to our potential work on the Therapeutic efficacy of AIH in persons with incomplete spinal cord injury. In other words, if individuals are highly spastic, it may indicate that their neuronal receptor sites are inaccessible, and increasing spinal cord serotonin levels may not be beneficial.
Eligibility
Inclusion Criteria:
- Age \>= 18
- Non-progressive spinal Cord injury at least 6 months prior
- Level of injury between C1-C8
- ISNCSCI ASIA classification C or D
- Measurable Spasticity
Exclusion Criteria:
- Pre-existing hypoxic pulmonary disease
- Positive Covid-Pneumonia diagnosis within 1 year of visit
- Uncontrolled hypertension \>140/90 mmHg
- Individuals who are currently pregnant/nursing or planning on becoming pregnant
- Individuals with a tracheostomy or who utilize mechanical ventilation
- A botulinum toxin injection to upper extremity musculature within the past 3 months
- Currently taking Baclofen
- Congestive Heart Failure
- Cardiac arrhythmias
- Uncontrolled diabetes mellitus
- Chronic obstructive pulmonary disease
- Emphysema
- Severe Asthma
- Previous myocardial infarction
- Carotid/intracerebral artery stenosis
- Orthopedic injuries or surgeries that impact the ability to use the upper extremity
- History of Epilepsy
