Comparison of lumbar interbody fusion performed with unilateral or bilateral pedicle screw

Currently, bilateral pedicle screw fixation is the standard of instrumentation, providing rigid fixation and an increased fusion rate. However, due to the excessive rigidity of the system, this instrumentation has been suspected to cause degeneration of adjacent segments. Alternatively, less rigid unilateral pedicle fixation is considered to be as effective as bilateral constructs. Few studies have compared unilateral and bilateral constructs in the treatment of lumbar degenerative disease. The purpose of this retrospective study was to evaluate possible differences between unilateral and bilateral pedicle screw fixation for single-level lumbar degenerative disease.Between October 2006 and October 2010, sixty consecutive patients were treated with unilateral pedicle screw fixation (28 patients) or bilateral pedicle screw fixation (32 patients) at the authors' institution. Oswestry Disability Index and visual analog scale scores showed a statistical difference between preoperative values and 3- and 6-month postoperative values (P<.05). Unilateral fixation resulted in shorter operative times and less intraoperative blood loss. No significant difference was found between the 2 fixation methods in terms of fusion rate and complication rate (P>.05).Lumbar interbody fusion with unilateral pedicle screw fixation was an effective and convenient method of treatment of single-level lumbar degenerative disease, with little surgical trauma.