Page 222 Guide to Pain Management in Low-Resource Settings

210 Mathew O.B. Olaogun and Andreas Kopf

(e.g., bone metastasis), infl ammation (e.g., spondyl- Diskogenic pain
odiskitis), instability (e.g., spondylolisthesis), or local Many studies have demonstrated that the intervertebral
compression (e.g., spinal or foraminal compression). disk and other structures of the spinal motion segment
It has to be repeated that generally the proportion can cause pain. However, it is unclear why mechanical
of back pain patients with specifi c pain is rather low back pain syndromes commonly become chronic, with
(around 5%). On the one hand, the pain causes men- pain persisting beyond the normal healing period for
tioned above should never be overlooked, but on the most soft-tissue or joint injuries. Infl ammatory factors
other hand, overinterpretation of radiographic results may be responsible for pain in some cases, in which epi-
should be avoided. dural steroid injections provide relief. Corticosteroids
As a rule of thumb, unrelenting pain at rest inhibit the production of arachidonic acid and its me-
should suggest a serious cause, such as cancer or in- tabolites (prostaglandins and leukotrienes), inhibiting
fection. Imaging studies and blood workup are usually phospholipase A (PLA ) activity. Levels of PLA , which
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mandatory in these cases and in cases of progressive plays a role in infl ammation, are elevated in surgically
neurologic defi cit, too. Other historical, behavioral, and extracted samples of human herniated disks. Further-
clinical signs that should alert the physician to a non- more, PLA may play a dual role, inciting disk degenera-
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mechanical etiology will require diagnostic evaluation. tion and sensitizing annular nerve fi bers.
Evidence for specifi c back pain might be the fol-
lowing diagnostic “red fl ags”: Radicular pain
• Colicky pain or pain associated with visceral Surprisingly, the pathophysiology of radicular pain is
function (or dysfunction). unclear. Likely etiologies include nerve compression
• History of cancer or fatigue, or both, and weight because of foraminal stenosis, ischemia, and infl amma-
loss. tion. Often, the cause of radiculopathy is multifacto-
• Fever or immunosuppressed status. rial and more complex than neural dysfunction due to
• History of older age and osteoporosis (with in- structural impingement. In clinical practice, structural
creased risk of fractures). impairment is usually considered to be responsible, if
• Progressive neurological impairment, or bowel infl ammation is found. Th erefore local epidural, often
and/or bladder dysfunction. para-radicular, steroid injections are used for therapy,
• Severe morning stiff ness as primary complaint. although their long-term eff ect is rather questionable.

Nonspecifi c pain Facet-joint pain
Evidence for nonspecifi c back pain might be the follow- Th e superior and inferior articular processes of adja-
ing diagnostic “red fl ags” (nonorganic signs and symp- cent vertebral laminae form the facet or zygapophyseal
toms): joints. Th ey share compressive forces with the interver-
• Dissociation between verbal and nonverbal pain tebral disk. After trauma or with infl ammation they may
behaviors. react with pain signaling, joint stiff ness, and degenera-
• Use of aff ective pain descriptions. tion. Interestingly, there is no strong relation between
• Little pain modulation, with continuous high pain radiographic imaging results and pain; therefore, the
intensity. diagnosis is strictly clinical (pain radiating to the but-
• Compensable cause of injury, out of work, seek- tocks and dorsal aspects of the upper limb, provoked
ing disability (confl ict of interest between com- by retrofl exion of the back and/or rotation). Unfortu-
pensation and wanting to be cured). nately, long-term eff ects of local steroid injections into
• Signs of depression (having diffi culty falling the joint or into the vicinity as well as electrical ablation
asleep, waking up early in the morning, loss of in- of the nerves innervating the joints (“medium bundle
terest, and loss of energy and drive, especially in block”) have failed to demonstrate long-term eff ects.
the fi rst half of the day) and anxiety (continuous
Sacroiliac pain
worrying and restlessness).
• Psychoactive drug requests. Th e sacroiliac joint receives its primary innervation from
• History of repeated failed surgical or medical the dorsal rami of the fi rst four sacral nerves. Arthrog-
treatments. raphy or injection of irritant solutions into the sacroiliac