The longer you are in pain, the more it messes with your head, begins to affect how you think about yourself, destroy healthy routines like exercise, how your relationships work.
“Chronic pain and stress are experienced by approximately 20% of the population. The cost is huge and dollar/pound/euro figures do not cover the impact on families and loss of creativity and productivity and its social impact. http://www.noigroup.com/en/Home
The areas that were injured become chemically and physiologically hyper-sensitized (the term “Allodynia” is used here), This is defined to central pain sensitization (increased response of neurons) following painful, often repetitive, stimulation. Allodynia can lead to the triggering of a pain response from stimuli which do not normally provoke pain.
even to the point that the pain may be triggered by gentle touch, old memories or movements, or emotional events and stresses completely unrelated to the actual physical problem.
A more scientific approach can be seen in this paper: Evidence Based Pain