A total of 5 randomized controlled trials containing 215 patients with multilevel degenerative lumbar spine disorders were included in this meta-analysis comparing unilateral pedicle screw fixation to bilateral pedicle screw fixation following spinal fusion. The primary outcomes of interest included the incidence of successful fusion, overall complications, dual tear, superficial wound complications, and screw-related complications. The secondary outcomes of interest included back and leg pain on a Visual Analogue Scale (VAS), the Oswestry Disability Index (ODI), and the Short-Form 36 health survey (SF-36) for physical function, general health, and mental health. Other outcomes included total blood loss, length of hospital stay, and operative time. All pooled primary and secondary outcomes were not statistically significantly different between the unilateral or bilateral pedicle screw fixation groups. However, pooled results demonstrated that operative time was significantly shorter in the unilateral pedicle screw fixation vs the bilateral group, whilst pooled total blood loss and length of hospital stay were not statistically significantly different between the two treatment arms. Finally, in a subgroup analysis of the unilateral pedicle screw fixation group comparing minimally invasive and open approaches, the pooled incidence of complications was not statistically significantly different between the minimally invasive and open approaches. However, a pooled composite outcome of operative time, blood loss, hospital stay, VAS, and ODI scores was statistically significantly different in favour of the minimally invasive approach (p=0.0004), but the heterogeneity was high (I^2=95.9%).