The study involved 164 subjects. Twenty-five controls with no spinal cord injury were recruited, as well as 139 paraplegics, who were divided into five groups based upon their level of injury: 24 subjects with complete lesions at the T4 level, 29 with complete injuries at the T11-T12 level, 35 participants with complete L1-L3 injuries, 42 with incomplete lesions at the T4 level and 9 subjects with T4 Brown-Sequard paralysis.