Pain
due to tissue injury, chronic pain is a self perpetuating feedback loop which involves changes in the
spinal cord transmission, hypersensitivity of nerves which fire off pain signals even when there is
no pain source, and chemical changes which occur inside the spine. Acute pain represents a
warning signal that something is wrong and triggers a withdrawal response, chronic pain instead is
perpetual, does not go away, and results in many many problems for patients. Sleep is decreased
due to chronic pain and when sleep is insufficient, pain is actually increased due to a reduction in
the inhibitory filters activity in the spine which in a non-sleep deprived person would stop
extraneous impulses from reaching the brain. Chronic pain often results in loss of employment, loss
of self esteem, reduction in sexual capabilities, reduced exercise and therefore weight gain, reduced
flexibility and therefore may be more prone to injury during times of increased activity, severe
emotional stress, clinical depression, and severe financial stresses.
Whereas acute pain is a symptom, chronic pain is a disease. Therefore the treatments are much
more complex in chronic pain as opposed to acute pain. Often multimodal pain therapies are
required including psychotherapies, physical therapy, injection therapy for desensitization of
painful structures, medications, and sometimes surgery. Treating chronic pain is far more similar
to treating a chronic condition such as diabetes than a smashed thumb. Often, chronic pain cannot
be cured just as there is no cure for diabetes, but there are adequate therapies which are employed
to manage the pain.
According to the IASP, 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. There are a large number of possible diagnoses which must be considered
in patients with chronic pain. These include the following:
Structural:
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, fascia
Discs-herniations, annular tears, bulges, internal derangement
Ligamentous-supraspinous, posterior longitudinal ligament tears
Functional: Posture, attitude, deconditioning, sleep deprivation, motivation, smoking (decreases
oxygen available to tissues), obesity
Emotional: 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 patient’s 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 with a
complete grasp of all available techniques and is unafraid to use them in combinations. Whereas
some physicians who claim to be pain management physicians are really “needle jockeys”, ie. they
refuse to use medication management and only stick needles into patients, these types of physicians
should be avoided since they have a very limited scope of practice which often does not meet the
long term needs of the patient. Of course if injections are being used for diagnostic purposes or
epidural steroids are tried when medically indicated, then the needle jockeys are actually
performing a useful temporary role in diagnosis and therapy. 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
(minimally invasive spine) 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, occasionally 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 here in Indiana.