The evaluation and treatment of patients with chronic pain that undermines function
and quality of life is facilitated by an understanding of the definition of pain
and an appreciation of its clinical characteristics.
The definition of pain according to the International Association for the Study
of Pain (IASP) is, “an unpleasant sensory and emotional experience, which we primarily
associated with tissue damage or describe in terms of such damage, or
both”. It should be noted that this definition combines the traditional concept
that pain reflects a sensory experience but also has an affective and cognitive
component These two components, especially the psychosocial factors affect
the sensation of pain and its effect on function and quality of life.
The IASP definition also indicates that the relationship between pain and tissue
damage is neither uniform nor constant. Based on the findings of the pain assessment,
the clinician may infer that the pain is either proportionate or disproportionate
to the tissue injury evident on examination (3). Patients with chronic
nonmalignant pain syndromes often complain of pain that exceeds demonstrable
tissue injury