OBJECTIVETo evaluate the therapeutic effects of lumbar spondylolisthesis by decompression, instrumentation and posterolateral fusion, and study the causes of the related complications and its method for the prevention.

METHODSOne hundred and sixty-five cases with grade I to II spondylolisthesis from February 1991 to May 2007 were retrospectively analyzed. All cases were treated by posterior lumbar canal decompression, reduction with pedicle screw system and fusion with posterolateral bone grafting. Among them,there were 55 male and 110 female with an average age of 53.6 years. Besides, one segment was involved in 161 cases and two segments involved in the rest of them.

RESULTSThe complications were divided into either intraoperative postoperative complications. Intraoperative complications were 5 cases (3.0%) there were 4 cases with dura tear and 1 case with nerve root injury. Postoperative complications were 18 cases (10.9%), there were 3 cases with cerebrospinal fluid leakage, 1 case with wound infection, 2 cases with hematoma,5 cases with transient neurological deficits, 1 cases with implant failures and 6 cases with pseudarthrosis formation.

CONCLUSIONGood clinical results of lumbar spondylolisthesis can be obtained by posterior reduction and fixation with pedicle screw system. However,operation skills and strict indications play an important role in the prevention of complications.