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Pain is a major health problem that significantly affects the qual-ity of life of patients. It has a significant impact on both the sufferers and the broader community, imparting high health costs, and economic loss to society. The consensus among clin-icians and researchers worldwide is that current strategies for the treatment of pain are inadequate. These inadequacies are even greater when chronic pain, which often accompanies chronic ill-nesses such as arthritis or nerve injury, is involved. Despite major advances in treatment strategies over the last two decades, pain management still remains a major challenge in arthritis; and even with treatment with current therapies, many patients still experience moderate-to-severe pain (Stein and Baerwald, 2013). Patients with rheumatoid arthritis report pain management as their highest priority (Whittle et al., 2013), and osteoarthritis is the leading cause of pain and physical disability in the elderl