What is the main difference between traumatic arthritis and degenerative arthritis?

Trauma or not. Both are forms of joint degeneration. In traumatic arthritis there is an identified injury to the joint which leads to the degeneration. In degenerative arthritis there is no injury identified that leads to the arthritis. In that situation there are dozens and dozens of possible causes for the degeneration.
Acccident trauma. Traumatic arthritis is caused by injury to the joints. Fractures contusions etc. Degenerative arthritis is similar to osteoarthritis which is usually the normal wear and tear on weight bearing joints.