Introduction to Chronic Pain Diagnosis
Chronic pain is an unpleasant sensory perception which lasts more than 3 months. Some definitions list chronic pain as that which lasts more than 6 weeks. There are many causes for chronic pain and many reasons for sustaining chronic pain long after the original pain source has healed. Low back pain is the most common type of chronic pain and will be emphasized in this paper. But even narrowing the scope to low back pain, one finds there are a large number of possible diagnoses. These include the following:>
Bone-compression fracture, spinal stenosis, spondylolisthesis, spondylosis, osteoporosis. Neural-nerve root entrapment, arachnoiditis, peridural fibrosis , peripheral nerve compression Joints-sacroiliac arthropathy, hip, facets, trochanteric bursa Myofascial-muscles, tendons, fascial Discs-herniations, annular tears, bulges, internal derangement, Ligamentous -supraspinous, posterior longitudinal ligament tears
Posture, attitude, deconditioning, sleep deprivation, motivation, smoking, obesity
Stress, depression, personality disorders, somatization
While there may be many methods used to arrive at a diagnosis, almost all begin with a thorough history. Of primary importance are trauma or injury and date of onset, location of most intense pain, referral location, factors that make it worse or better, past treatments including physical therapy and specific type of physical therapy. All MRIs and X-rays may be important, so it necessary to know where and approximately when they were taken.
Pain map drawings can be very helpful since these can localize the pain better than a descriptor. It is very difficult for most patients to accurately tell a doctor where back pain is localized. Much of this is due to the lack of anatomical knowledge of the back and overlying structures.
The physical exam is paramount and should include motor, sensory testing, gait, balance, mobility, and palpation. It is used as a confirmatory test for the history.
MRIs are inaccurate at least 25% of the time in the cervical spine and at least 10% of the time in the lumbar spine. The MRI sees discs, nerve roots, bone, but does not see spine ligament tears, muscle pain, etc., and has no functional component. It sees anatomy but cannot correlate anatomy with pain.
Diagnostics needed for different pain syndromes are complex and may require several visits with diagnostic procedures to help rule out specific types of pain syndromes. Often pain sources overlap creating a difficult diagnostic dilemma. Sometimes there are more than one source of pain with one pain source being secondary to another. The timing and onset of pain can give information about the domino effect: one pain source leading to a change in the posture or gait thereby causing another pain which causes another pain. Sometimes psychological evaluation will be incorporated in order to form a complete picture of the patientís pain source and response. Depression and lack of sleep drastically increase pain levels at the spinal cord level.
Different physicians see pain largely as being based on their specialty. For instance, rheumatologists look for a joint or connective disease origin for pain while a neurosurgeon focuses on disc and nerve sources. If the source of pain is not evident within the confines of their training, in some cases the patient is erroneously told that there is nothing wrong with them. This type of statement reflects the lack of education of the physician more than the lack of pathology in the patient. Often, a patient will wander from physician to physician over a several year period until a well trained, broad perspective physician can make the proper diagnosis. A pain management physician or algologist, is a broad based physician who practices the discipline full time. It is not an anesthesiologist doing part time pain blocks only, a family doctor who prescribes narcotics and therefore touts himself as a pain management doctor, or a physiatrist who may do EMGs but does not have the expertise for advanced treatments. Most algologists will be board certified by one of the subspecialty boards in pain management or pain medicine. They may have come from one of many primary disciplines, but most will have completed a residency in anesthesiology, neurology, or physical medicine and rehabilitation. Algologists see a broad spectrum of disease and are equipped with advanced therapeutic and diagnostic means. MIS surgeons are minimally invasive spine surgeons who perform spinal surgery procedures through small scopes or needles. They may be orthopedic spine surgeons, neurosurgeons, or algologists. MIS surgeons believe in reduction of tissue damage, faster return to work times, and in minimization of scar tissue as means to improved outcomes.
Finally, on occasion, it may be impossible to acquire a definitive diagnosis. In such cases, therapy may be empirical or palliative until technology advances sufficiently for treatment of the source of pain becomes possible. We strive to make these advances possible and are on the leading edge of pain management nationwide.