SCI is typically caused by a traumatic blow to (or penetration of) the spine that fractures or dislocates vertebrae. The trauma causes the resulting bone fragments, material in the spinal discs, or ligaments to bruise or tear into spinal cord tissue, damaging it or, in some cases, severing the cord entirely and resulting in partial or complete paralysis. NICHD supports basic research related to SCI and promotes the development and application of devices, including prosthetics and wheelchairs, and the use of biomechanical modeling to improve the quality of life for people regardless of their injury.