Transcutaneous Electrical Spinal Stimulation to Restore Upper Extremity Functions in Spinal Cord Injury

Inclusion Criteria: * Cervical (C7 or higher) spinal cord injury at least 1-year duration * Incomplete spinal cord injury (American Spinal Injury Association Impairment Scale (AIS) C or D) * Between 21 and 70 years of age * Difficulty with hand functions in activities of daily living (e.g. dressing, grooming, feeding) * Stable medical condition without cardiopulmonary disease or frequent autonomic dysreflexia that would contraindicate participation in upper extremity rehabilitation or testing activities * Capable of performing simple cued motor tasks * Ability to attend 2 to 5 sessions of weekly physical therapy sessions and testing activities * Adequate social support to be able to participate in weekly training and assessment sessions for the duration of 6 months within the study period. * Ability to read and speak English Exclusion Criteria: * Autoimmune etiology of spinal cord dysfunction/injury * History of additional neurologic disease, such as stroke, multiple sclerosis, traumatic brain injury, etc. * Peripheral neuropathy (diabetic polyneuropathy, entrapment neuropathy, etc.) * Rheumatic diseases (rheumatoid arthritis, systemic lupus erythematosus, etc.) * Significant medical disease; including uncontrolled systemic hypertension with values above 170/100 mmHg; cardiac or pulmonary disease; uncorrected coagulation abnormalities or need for therapeutic anticoagulation. * Active cancer * Cardiovascular or musculoskeletal disease or injury that would prevent full participation in physical therapy intervention * Unhealed fracture, contracture, pressure sore, or urinary tract infection or other illnesses that might interfere with upper extremity rehabilitation or testing activities * Any condition that would render the patient unable to safely cooperate with the study tests as judged by the screening physician * Pregnancy * Tendon or nerve transfer surgery in the upper limbs * Botulinum toxin injections in the prior 6 months * Dependent on ventilation support * Implanted stimulator (e.g. vagus nerve stimulator, pacemaker, cochlear implant, etc). * Has depression or anxiety based on Patient Health Questionnaire and General Anxiety Disorder-7 item Questionnaire * Diagnosed with syringomyelia * Alcohol and/or drug abuse. * Cognitive impairment based on Short Portable Mental Status Questionnaire * Unable to read and/or comprehend the consent form. * Unable to understand the instructions given as part of the study.