It is as much of the business of a physician to alleviate pain, and to smooth the avenues of death, when unavoidable, as to cure diseases.
JOHN GREGORY (1725–73), LECTURES ON THE DUTIES AND QUALIFICATIONS OF A PHYSICIAN
Pain is the capital symptom of humans—the great hallmark of disease—the signal par excellence to the patient and doctor that all is not well.
In modern medicine the successful management of chronic pain, in particular, still poses a great challenge. Its management or mismanagement is a yardstick of the excellence of that important bond—the doctor–patient relationship.
Pain is a multifactorial problem. The suffering patient must not only deal with the painful sensation itself but also cope with its possible serious significance.
Does chest pain imply a pending heart attack?
Does chronic ache or acute pain signify cancer?
Does ‘whiplash’ imply neck pain to the grave?
Chronic pain is the most challenging problem. It must be emphasised that it always starts as an acute episode and that back pain accounts for the majority of cases of chronic pain encountered in general practice.
Pain is defined as ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage’. The box below defines the variety of types of pain.
Glossary of terms1
Allodynia Pain due to a stimulus that does not normally provoke pain.
Mechanical—light touch feels painful.
Temperature—hot/cold stimulus (normally not painful) is painful.
Anaesthesia dolorosa Pain in an area or region that is anaesthetic.
Analgesia Absence of pain in response to stimulation that would normally be painful.
Breakthrough pain Pain which occurs between regular doses of analgesics and reflects increase in pain level above set baseline
Causalgia A syndrome of sustained burning pain, allodynia and hyperpathia after a traumatic nerve lesion, often combined with vasomotor and sudomotor dysfunction and later trophic changes (now known as complex regional pain syndrome II).
Central pain Pain associated with a lesion of the central nervous system.
Dysaesthesia An unpleasant abnormal sensation, whether spontaneous or evoked (e.g. formication—a feeling like ants crawling on the skin, burning, tingling).
Hyperaesthesia Increased sensitivity to stimulation, excluding the special senses.
Hyperalgesia An increased response to a stimulus that is normally painful (i.e. painful stimulus feels much more painful than expected, such as firm finger pressure).
Hyperpathia A painful syndrome, characterised by an increased reaction to a stimulus, especially a repetitive stimulus, as well as an increased threshold for sensory detection.
Hypoaesthesia Decreased sensitivity to stimulation, excluding the special senses.
Hypoalgesia Diminished pain in response to a normally painful stimulus.
Incident pain Pain that occurs on, or is exacerbated by, an activity (e.g. coughing, wound dressing, movement, weight-bearing).