Is stabilisation of contralateral side necessary while using unilateral approach in lumbar fusion surgery at 2 adjacent levels?

Generally, fusion supplemented with bilateral pedicle screw fixation is the widely accepted method of stabilisation to create an ideal environment for fusion of the
unstable and the degenerated disc area. Rigid internal fixation by bilateral pedicle screw fixation has its shortcomings in the form of adjacent lumbar segment degeneration and implantrelated osteoporosis. Moreover, bilateral fixation was associated with longer surgical time, greater blood loss and involving greater costs. A relatively less rigid fixation in the form of unilateral pedicle screw fixation could reduce the stress shielding and adjacent intervertebral disc degeneration caused by bilateral pedicle screw fixation. Biomechanical studies supported his concept stating that unilateral pedicle screw fixation was sufficient to maintain the stability of the
spine. We performed this meta-analysis to compare the safety of unilateral with bilateral instrumented fusion in two-level degenerative disorders of lumbar spine.