Injuries to the cervical spine, including C3 and C4, are the most severe of all spinal cord injuries. The greater the level of damage to this spinal region, the more functional loss that results in the central nervous system. Survivors are likely to experience limited mobility in the flexion and extension (the movement of the chin toward the chest, and the backward movement of the head, respectively) of the neck, as well as breathing difficulties or need for a ventilator, quadriplegia, and difficulty or loss of bladder or bowel function. Unfortunately, there currently is no treatment to completely reverse the damage from spinal cord injuries ac C3-C5. However, some individuals have had experienced great success in their recoveries, including Dana, who recovered full function of the muscles in her hands and arms.