Unilateral versus bilateral pedicle screw fixation in lumbar interbody fusion: a meta-analysis of complication and fusion rate.

Unilateral or bilateral pedicle screw (PS) fixation in lumbar interbody fusion remains controversial. The aim of this study was to evaluate the complication and fusion rate for both surgical techniques based on published studies. Pubmed, Cochrane Library and Embase Databases were searched to identify studies reporting complication rate or fusion rate of unilateral and bilateral PS fixation in lumbar interbody fusion. Outcomes of complication rate and fusion rate were analyzed. Seven articles including 501 patients were identified fitting inclusion criteria. There was no significant difference of total complication rate (RR 1.17, 95% CI: 0.73-1.89, P=0.51) and fusion rate (RR 0.94, 95% CI: 0.87-1.01, P=0.07) between the two groups. However, the fusion cage migration rate was significant higher (RR 2.41, 95% CI: 1.06-5.46, P=0.04) in unilateral group than bilateral group. In conclusion, the available evidence indicated that both unilateral PS fixation and bilateral PS fixation could get satisfactory fusion rate and complication rate. But unilateral PS fixation had more fusion cage migration than bilateral PS fixation in patients who undergo lumbar interbody fusion.