Types of Pain

CNMP is a biological–psychological–sociological phenomenon. All aspects of these problem areas must be appropriately diagnosed and treated. To not do so will prevent a good outcome from treatment – secondary to lack of amelioration of pain and inability of the patient to regain function. A major differentiating factor between acute-pain patients and those with CNMP is that the latter typically do not have significant physiological objective findings on examination that correlate to the patients’ complaints. Those that have objective findings may not appear to have findings that would support the degree of their subjective complaints of chronic, severe pain. These patients are numerous – statistics indicate that the approximate total number of such patients in the US is at least 70 million. The most common forms of CNMP include:

• myofascial pain syndromes;
• fibromyalgia;
• neuropathic (nerve-related) pain;
• radiculopathies (chronic central nerve impingement by a disc in the spinal column);
• failed back syndromes (continued pain after one or more neck or mid or low back surgeries);
• complex regional pain syndrome (formerly called reflex sympathetic dystrophy); and
• sympathetically maintained pain – secondary to autonomic nervous system dysfunction, arthritis and chronic headache.

The biological–psychological–sociological phenomenon that encompasses CNMP is most time-, cost- and clinically effectively treated within the framework of an interdisciplinary pain management programme.³ Such a programme consists of the physician medical director (typically a neurologist or physiatrist), who makes diagnoses and deals with medical management, including neuropharmacological care; nurses, who act as both internal case managers and educators; psychologists, who deal with cognitivebehavioural therapy, biofeedback neuromuscular reeducation and other aspects of individual and group treatment; and rehabilitation professionals, including physical therapists and occupational therapists. Other members of a pain management team may include social workers, vocational specialists and alternative medicine specialists. Published research, including evaluated evidence-based medicine with metaanalyses, has demonstrated the clinical effective-ness, along with the time- and cost-effectiveness, of these programmes.^4–8 Unfortunately, very few chronicpain patients, possibly up to 6%, obtain treatment in an interdisciplinary pain medicine programme.⁹ For the treatment of certain chronic pain conditions, neurostimulation may be the appropriate approach (see separate text box).

The typical pain patient is seen first frequently by their primary care physicians, a generalist or family physician. Tests are performed, probably including magnetic resonance imaging (MRI) and/or computed axial tomography (CAT) scans. If these clinicians are unable to help the patients, especially if any of these tests are positive, they are sent for a consultation to an orthopaedist or neurosurgeon, and more tests may be performed. It should be remembered that many people without complaints of pain have an ‘abnormal MRI or CAT scan’ of the cervical or lumbosacral spine.¹⁰ If surgery is not performed, the patient is typically sent to an interventional anaesthesiologist, who will perform multiple treatments (epidural steroid injections, facet/medial branch nerve blocks and radiofrequency neurolysis/rhizotomies). Often, these patients receive only a temporary decrement in their pain, which will soon return to baseline levels. The interventionalists may place the patients on narcotic pain medication or send them back to their referring physician for such pain medications.