In the past, complete laminectomy and facetectomy was associated with a certain rate of postoperative instability, leading some to advocate simultaneous fusion. In comparing decompression alone with fusion, Grob et al7 compared 45 patients randomized to decompression, single-level fusion and multi-level fusion arms. They found no significant difference among the three groups, concluding that “in the absence of [preoperative] segmental instability, arthrodesis is not necessary after decompression of the lumbar spine.”
My personal approach to lumbar stenosis is to advocate weight loss in those patients with moderate abdominal girth and to offer a trial of up to three lumbar epidural steroid injections. Physical therapy may be helpful in training patients in abdominal toning exercises, but there may not be much benefit to more than a few weeks of therapy; the exercises can be done at home just as well, and neither massage nor surface therapies address the root causes. I generally do not recommend traction therapy. Some less obese patients may benefit from an abdominal corset to allow a slightly less arched posture when standing. The use of a walker, cane or trekking poles can achieve the same result temporarily, until weight loss can be achieved.
Practically, however, hardly any of the elderly patients with lumbar stenosis can successfully lose enough weight or gain enough abdominal tone to make a difference. If steroid injections and a few months of these other conservative measures do not suffice, then decompressive surgery should be considered.
The general principles in designing an appropriate operation involve minimizing risk while addressing the presenting symptoms of the patient. Since modern imaging can reveal many more abnormalities than might ever become symptomatic, an appropriately designed operation can reasonably leave behind a good deal of pathology. Bearing these principles in mind might preclude a great deal of the increased fusion surgery noted at the beginning of the article, and bring our practice more in line with that of other countries.
In the case of classic lumbar stenosis and neurogenic claudication, the majority of cases can be managed with decompressive laminectomy alone. With regard to number of levels, my personal experience matches that of Costa et al8 in which stenosis was present at one level in 76% of their patients, two levels in 22% and three levels in only 1%. The addition of a fusion can be limited to cases of frank instability, scoliosis and symptomatic degenerative disc disease. As in decompression, fusion should rarely require the incorporation of more than two disc levels, unless scoliosis is present.
Finally, keep in mind that this is a chronic condition, progressing over months and even years. There is usually time for the patient to obtain a second opinion prior to having surgery. This is particularly important if extensive fusion surgery is being considered.