Diagnosing regional pain: the view from primary care.

There is a general lack of new evidence on which to base practical and useful diagnostic classifications of regional musculoskeletal pain for primary care. However, the 'red flag' system, developed and now disseminated successfully in the management of low back pain, seems to be applicable to the initial management of other regional pain. In this scheme, signs and symptoms of serious disease are sought, and their presence is the indication for the investigation or referral of individual patients. In their absence, the low predictive value of many signs, tests and even diagnostic labels argues against their routine use in primary care. Simple decisions based on separation into articular versus non-articular, and acute versus chronic, are favoured by the most recent expert consensus statements. In addition, the presence or absence of more widespread pain, and of other non-specific features of chronic pain, is likely to be helpful in managing regional syndromes. Prospective studies of the prognostic value of symptoms, signs and diagnostic labels remain a research priority in this field.