Low back pain disorders: lumbar fusion?

The role of lumbar spine arthrodesis in the treatment of low back pain disorders remains a highly disputed and controversial subject. There are no clear-cut indications for lumbar spine fusion in lumbar degenerative disc disease. In fact, lumbosacral fusion when added to appropriate decompressive surgery has failed on careful statistical analysis to significantly improve the results over decompressive surgery alone. Moreover, in several large series in the literature of lumbosacral fusion in conjunction with discectomy, the results in patients who developed a pseudoarthrosis did as well as matched cases who obtained an excellent arthrodesis. These results should not be surprising since there does not appear to exist a generally accepted operational definition of mechanical (lumbar instability) pain. The author, however, is of the opinion that lumbosacral arthrodesis will prove to have a definite, albeit small, role in the management of the intractable and incapacitating low back pain disorders. This is based on personal clinical experience and the belief that the phenomenon of intractable and incapacitating mechanical low back pain syndromes do exist. Carefully performed prospective clinical studies are requisite to define the mechanical low back pain syndrome and the role of lumbar arthrodesis in the treatment of the low back pain disorders. Given our present limitations, the author suggests that lumbosacral arthrodesis be reserved for patients suffering spondylotic low back pain syndromes who have the following characteristics: intractable and disabling pain; primary complaint of segmental mechanical pain; radiologic evidence consistent with "instability"; minimal or no segmental disease above proposed site of arthrodesis; and minimal or absent psychosocial-economic pain.