Is the only difference between acute and chronic the scar? What else happens to the cord after the acute stage? Also, how long does the “acute” stage last? 2 weeks? couple days? 1 month?

fine the “acute” phase of spinal cord injury as the period during which damage may be continuing.

“Subacute” is when the spinal cord is beginning to resolve the damage and starting repair. There is then a period of recovery that may take years. At the end of that period, when recovery has stabilized and the condition is stable, I would use the descriptor “chronic” spinal cord injury.