Clinical and radiographic analysis of unilateral versus bilateral instrumented one-level lateral lumbar interbody fusion

Abstract

Lateral lumbar interbody fusion (LLIF) is a widely applied and useful procedure for spinal surgeries. However, posterior fixation has not yet been decided. We compared the radiographic and clinical outcomes of unilateral versus bilateral instrumented one-level LLIF for degenerative lumbar disease. We conducted a prospective cohort study of 100 patients, who underwent unilateral (group U) or bilateral (group B) instrumented one-level LLIF for degenerative lumbar disease. Forty-one patients in group U were undergoing unilateral pedicle screw instrumentation, and 59 patients in group B were undergoing bilateral pedicle screw instrumentation. Clinical characteristic and demographic data before surgery were compared. The intraoperative data, including operative time with changes in positions, intraoperative blood loss, and X-ray exposure time, as well as the perioperative data, including postoperative hospital stay and clinical and radiographic data were compared. As a result, Group U required a significantly shorter operating time than group B. The subsidence grade and fusion rates exhibited no significant differences in the postoperative radiographic evaluation. Group U had better results in clinical assessments than group B. However, group U required more additional surgeries owing to complications.

Correlation between Preoperative Serum Levels of Calcium, Phosphate, and Intact Parathyroid Hormone and Radiological Outcomes in Spinal Interbody Fusion among End-Stage Renal Disease Patients

“…The calculated mean kappa coefficient value for the interobserver reliability was 0.91, and the intraobserver reliability after 8 weeks was 0.94. This represents near perfect agreement between the observers and the time points based on Landis and Koch's measurements [15].…”

“…Subsidence was measured from standing neutral lateral radiographs with parallel end-plates at the index level. The degree of the vertebral body collapse around the disc space was categorized according to the grading system first described by Marchi et al: grade 0, 0-24% collapse; grade I, 25-49% collapse; grade II, 50-74% collapse; and grade III, 75-100% collapse [14,15]. Radiographic ASD in the TLIF group was defined as follows: (1) development of spondylolisthesis of >4 mm, (2) segmental kyphosis of >10 • , and (3) adjacent disc collapse [16].…”

Cadaveric biomechanical analysis of multilevel lateral lumbar interbody fusion with and without supplemental instrumentation

“…The added instrumentation in LLIF is to further reduce motion and increase a construct’s ability to aid in fusion [ 19 ]. The optimal supplemental instrumentation for LLIF had been evaluated by many prior biomechanical and clinical studies [ 4 , 20 , 21 ]. In a three-dimensional finite element study of comparing the kinematic stability afforded by stand-alone cages with those supplemented by lateral plate as well as unilateral or bilateral pedicle screw/rod in a multilevel LLIF construct with simulated osteoporosis, the authors reported stand-alone cage (10–75.1% ROM reduction) and lateral plate (23.9–86.2% ROM reduction) provided inadequate ROM restriction for the multilevel LLIF constructs, whereas lateral cage with BPS (66.7–90.9% ROM reduction) or UPS (45.0–88.3% ROM reduction) fixation provided favorable biomechanical stability [ 13 ].…”

Safety and efficacy of unilateral and bilateral pedicle screw fixation for lumbar degenerative diseases by transforaminal lumbar interbody fusion: An updated systematic review and meta-analysis

“…UPSF provides biomechanical stability similar to BPSF in post-fusion level 1 TLIF ( 37 ). Currently, the consensus among clinicians is that UPSF should be limited to single-segment posterior lumbar interbody fusions rather than extending to multi-segment fusions due to insufficient fixation strength ( 32 , 38 ). However, due to the lack of evidence of complications such as cage subsidence and adjacent segment disease, as well as the inherent asymmetry and reduced strength of this system, the use of unilateral instruments may result in disconnection, metal failure, or cage migration ( 39 ).…”