Journal of spinal disorders
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Combined anterior and posterior fusion with posterior instrumentation may be indicated in the treatment of select cases of L5-S1 spondylolisthesis. The instrumentation, however, is expensive and usually bulky, occasionally requiring removal. In an effort to avoid these problems, an L5-S1 paralaminar screw technique was developed for posterior stabilization after an L5-S1 anterior interbody fusion. ⋯ Compared with other posterior instrumentation systems, this screw fixation is inexpensive and does not require implant removal. The disadvantages of the method are the degree of difficulty of the procedure and the limited clinical application to cases of L5-S1 spondylolisthesis with corrected residual slips of 25 to 50-60%. The procedure is technically demanding and should be limited to those surgeons who are comfortable with the method.