This is the final stage of subluxation degeneration. At this point, you experience a marked decrease in the quality of life, and longevity is lessened. Neurological and bone damage previously suffered are permanent and the vertebra are fused. Range of motion may be severely limited and a number of other health issues may present.
However, with proper chiropractic care, the patient can sometimes relieve pain and improve overall nervous system function enough that they can still enjoy living life as independently as possible. This is true even at phase IV.