That depends on the amount of the force that has been applied, the mechanism of the injury, and the underlying conditions (osteoporosis, rheumatoid arthritis, ankylosing spondylitis etc.)
The symptoms and signs vary greatly from simple pain and myofascial stiffness, to very severe neurologic disability.
Fracture & Epidural Hematoma
Compressed fracture and spinal cord
Concerning the treatment, it is either conservative or surgical, and this is an area of great debate and multiple methods. Nevertheless, the goal of the treatment is to establish the best possible functionality, as soon as possible, with the minimum reductant pain.