[Mechanisms of myofascial pain].

The aim of this paper is to review available data and current hypotheses concerning myofascial pain syndrome pathophysiology and implications for clinical practice. A muscular hypothesis has been proposed for episodic and chronic tension headache as well as for myofascial syndrome and fibromyalgia. These different syndromes may be compared as, besides their frequent combination, they have common features characterized by spontaneous pain, painful points, and lack of objective findings.

[Principles of organization of a center for pain evaluation and treatment].

Since the development during the sixties of the pioneer pain clinics in the United-States, the need of a pluridisciplinary approach of the chronic pain patient has progressively compelled recognition. The principles of organization of this new care units--the pin center--are now clearly determined. It has become classic to compare acute pain as a warning symptom with chronic pain as an illness in itself with its constellation of psychosocial factors.

[Clinical approach in patients with chronic pain].

In the case of a patient having persistent pain for 3 to 6 months, the physician needs to structure the various data obtained over that time. We propose an approach which analyzes pain according to various independent axes, in particular somatic and psychosocial. Correct diagnosis of the pathophysiological mechanism of pain (excess nociception, neurogenous, maintenance by the sympathetic nervous system, or muscular) is required in order to direct appropriate symptomatic treatment.

[Need of risk reevaluation in morphine dependence in pain patients].

It is commonly recognized than opioids analgesics have an major place in the treatment of pain. In spite of guidelines, opioids drugs remain underutilized in chronic cancer pain and acute severe pain. Among the possible factors, involved in the insufficient use of opioids drugs, is the fear (opiophoby) of physicians, nurses, patients and family to induce or to maintain an addiction.