The multiply operated lumbar spine.

In conclusion, it needs to be stressed that the physician should take an organized approach in evaluating the multiply operated spine patient. The origin of the problem in most patients is a faulty decision to perform the original procedure. Further surgery on an "exploratory" basis is not warranted and will lead only to further disability. Another operation is indicated only when there are objective findings to justify it. Multiply operated back patients need a total assessment. The cause of each patient's complaints must be accurately localized and identified. In addition to the orthopaedic evaluation, the patient's psychologic and general medical status must be thoroughly investigated. Once the spine is identified as the source of his symptoms, specific features should be sought in the patient's clinical history, physical examination, and roentgenographic studies. The number of previous operations, characteristics of the pain-free interval, and predominance of leg versus back pain are the major historical points. The neurologic examination and the presence of a tension sign are the important physical findings. Plain roentgenograms, motion films, metrizamide myelography, and computerized axial tomography have a specific place in the work-up. When all the information is integrated, the physician can separate patients with mechanical problems from those with arachnoiditis. If repeat surgery is undertaken, the approach must be a new level because the dura has no osseous protection at the previous laminectomy site. The midline scar tissue should be left intact and the nerve roots exposed laterally. Finally, the surgeon should be prepared to repair a dural tear, for this is the most common complication of a repeat laminectomy.