Low back pain may be a major symptom in patients with hysteria, malingering, anxiety, depression, and hypochondriasis as well as in many persons whose symptoms do not conform to any of these psychiatric illnesses. It is good practice to assume that pain in the back in such patients may signify disease of the spine or adjacent structures, and this should always be carefully sought. However, even when some organic factors are found, the pain may be exaggerated, prolonged, or woven into a pattern of invalidism because of coexistent primary or secondary factors. This is especially true when there is the possibility of secondary gain (notably workers’ compensation or settlement of personal injury claims). Patients seeking compensation for protracted low back pain without obvious structural disease tend, after a time, to become suspicious, uncooperative, and hostile toward their physicians or anyone who might question the authenticity of their illness. One notes in them a tendency to describe their pain vaguely and a preference to discuss the degree of their disability and their mistreatment at the hands of the medical profession. The description of the pain may vary considerably from one examination to other. Often also, the region(s) in which pain is experienced and its radiation are nonphysiologic, and the condition fails to respond to rest and inactivity. These features and a negative examination of the back should lead one to suspect a psychologic factor. A few patients, usually frank malingerers, adopt bizarre gaits and attitudes, such as walking with the trunk flexed at almost a right angle (camptocormia), and are unable to straighten up. Or the patient may be unable to bend forward even a few degrees, despite the absence of muscle spasm, and may wince at the slightest pressure, even over the sacrum, which is seldom a site of tenderness unless there is pelvic disease.
The depressed and anxious patient with back pain represents a difficult problem. The disability seems excessive for the degree of spinal malfunction. Anxiety and depression may become important components of the back syndrome and the patient may ruminate about an undiagnosed cancer or other serious illness. In these circumstances, common and minor back ailments—for example, those caused by osteoarthritis and postural ache—are enhanced and rendered intolerable. Such patients are still subjected to unnecessary surgical procedures. It is not clear if one can depend on the diagnostic features of a response to drugs that alleviate depression.
Among the most difficult patients to manage are those with chronic low back pain who have already had one or more laminectomies and sometimes a fusion without substantial relief. In one perhaps dated but large series of patients operated on for proven disc prolapse, 25 percent were left with troublesome symptoms and 10 percent required further surgery (Weir and Jacobs). In such patients our suggestion has been to repeat the MRI or CT myelography. In a fair number it will be found that the disc has reruptured, or that there is unaddressed lateral recess stenosis, or that a disc or degenerative disease has appeared at the level just above, or less frequently, below the site of previous decompression. Whether decompression with fusion reduces or exaggerates the frequency of this last problem is not clear. EMG and nerve conduction studies, searching for evidence of a radiculopathy, are also helpful. If there is evidence of a radiculopathy but no disc material, or only scar tissue is seen on MRI, one cannot know whether the pain relates to injury from the initial rupture or is the aftermath of surgery (see reviews by Quiles et al and by Long).