Current Concepts in the Understanding of Pain in the Rheumatic Diseases

Although musculoskeletal pain is the commonest cause of chronic pain and one of the most common presenting features in rheumatology, it remains poorly managed. The burden of musculoskeletal pain is estimated to have increased between two and fivefold in the last 40 years. Pain in musculoskeletal disease can be inflammatory or degenerative and is often an essential part of the condition and is used by both patients and physicians to assess disease progress. The mechanisms of pain perception and pathology are varied and complex involving a distributed network from the periphery to the brain. This results in peripheral and central sensitisation following injury. In chronic pain this is further complicated by maladaptive neuroplasticity and psychological influences resulting in fear-avoidance. Recent advances in neuroimaging and genetics have aided a deeper understanding of the underlying processes. Both individual genes accounting for monogenic disorders and those with polygenic influences have been identified. The basic science of nociception, the current understanding of genetic influences, clinical aspects of pain management and evaluation and the practical application of these in understanding pain related to specific rheumatological conditions is reviewed.