Sagittal Parameters After Mono Segmental Lumber Fusion: Interbody Versus Postrolateral Fusion

The term "spondylolisthesis" refers to slipping of a vertebra relative to an adjacent vertebra,and there are two mean types degenerative and lytic : Degenerative spondylolisthesis is secondary to osteoarthritis leading to facet incompetence and disc degeneration.This condition allows anterior translation of one vertebra on another. Spondylolysis is the break in the pars interarticularis and is the precursor of lytic spondylolisthesis which associated with a pars fracture When nonoperative care fails and surgery is being considered, the type of fusion should be tailored to the specific pathology being treated.So there are different operations to correct this instability like postrolateral fusion (PLF) and posterior lumber interbody fusion (PLIF) PLF decreases segmental motion in the posterior column, which presumably reduces facet joint pain.Theoretical advantages of PLIF include decompression of exiting nerve roots by distraction of the collapsed disc space, achievement of optimal fusion in relation to the load-bearing capacity of the vertebral bodies and possibly attainment of a better fusion rate

Inclusion criteria

• Adult patient older of 18 years old.
• Patients with lytic spondylolisthesis
• Low grade spondylolisthsis 1,2

Exclusion criteria

• Traumatic spondylolysis
• Previous spine surgery.
• Patient younger 18 years old
• High grade spondylolisthsis 3,4,5 - multiple levels spondylolithises