If you cannot move your legs but came move your arms like before, your spinal cord is hurt in your back (T1 and below) and you would be termed in medical language as a paraplegic.

If you cannot move your legs and arms both then your spinal cord is injured in your neck area (C1 to C8) and you would be termed as a tetraplegic. The closer the injury of the spinal cord to the brain fewer parts and systems of the body work normally.