Neuroplasticity mechanisms in the pathophysiology of chronic pain.

Chronic pain is a widespread healthcare problem with great impact on mental health, professional and family life of the patient. It can be a consequence of many disorders; however, its pathogenesis has not yet been fully understood. Neuroplasticity is the ability of the nervous system to adapt to different changes and it is present throughout life, not only in prenatal period, infancy and childhood. However, in the pathophysiology of chronic pain, neuroplasticity shows its "dark side". Due to the central sensitization process, noxious stimuli can produce chronic pain or misinterpretation of non-noxious stimuli (secondary hyperalgesia and allodynia). These changes occur at the level of brain cortex as well at peripheral nerves and receptors. This review summarizes a significant portion of literature dealing with neuroplasticity processes in well known chronic pain conditions such as migraine, chronic posttraumatic headache, low back pain, fibromyalgia, and others. The relevance of this topic lies in providing a new insight in the pathophysiology of chronic pain, while also offering a possibility of new therapeutic approaches including not only pharmacological agents.