Spinal Cord Stimulation for Respiratory Rehabilitation in Patients With Chronic Spinal Cord Injury

Inclusion Criteria: * At least 18 years old; * stable medical condition; * no painful musculoskeletal dysfunction, unhealed fracture, contracture, pressure sore or urinary tract infection that might interfere with respiratory training or stimulation; * no clinically significant depression, psychiatric disorders or ongoing drug abuse; * non-progressive SCI (no negative change in the neurological level and motor-completeness assessed during screening when compared to the neurological status assessed at 6-mo period after injury or at least 6 months prior to the screening), non-ventilator dependence, motor-complete SCI according to the American Spinal Injury Association Impairment Scale (AIS) grade "A" or "B" above T5 spinal level; * sustained SCI at least 12 months prior to entering the study; * compared to the normative values for healthy population, at least 15%-deficit in pulmonary function outcomes (FVC and FEV1) as detected by screening spirometry. Exclusion Criteria: Participants will be excluded from the study if there is a presence of * major pulmonary or cardiovascular disease, * ventilator dependence, * endocrine disorders, * malignancy, * marked obesity, * deep vein thrombosis, * HIV/AIDS-related illness, * secondary hypotension (anemia, hypervolemia, endocrine and neurological diseases), * major esophageal/gastrointestinal problem or other major medical illness contraindicated for respiratory training or testing. During screening, the potential participant will be asked whether she is pregnant or planning to become pregnant during the study period. Pregnant women are excluded from this study, as the risk to the fetus is unknown. No pregnancy test or birth control regimen will be required.