Early clinical and radiological results of unilateral posterior pedicle instrumentation through a Wiltse approach with lateral lumbar interbody fusion.

BACKGROUND: To assess the clinical outcomes of 44 patients who underwent single-level lateral lumbar interbody fusion (LLIF) with unilateral pedicle screw instrumentation through a paramedian Wiltse approach.

METHODS: Demographic, comorbidity, clinical assessment, peri-operative, and complication data were assessed. Visual analog scale (VAS), Oswestry disability index (ODI), and short form-12 (SF-12) were used to assess clinical outcomes. Post-operative plain radiographs were assessed for subsidence, cage migration, and fusion.

RESULTS: Average age of patients at surgery was 60.8±10.6 years (range, 32-79 years), with 15 males and 29 females. Recombinant human bone morphogenic protein-2 (rhBMP-2) was used in 32 cases (73%) and 13 posterolateral fusions (30%). Average duration of surgery was 195.2±36.9 minutes (range: 111-295 minutes), with an estimated blood loss of 159.3±90.8 cc (range, 50-500 cc). There were no intra-operative complications. Average length of hospital stay was 4.2±2.5 days (range, 2-13 days). Four patients (9%) experienced neurological deficit, 2 of which resolved by 3-month follow-up and 2 of which improved but did not resolve by final follow-up at 11 and 16 months. There was significant improvement in VAS (P<0.001), ODI (P<0.001), and SF-12 physical component (P<0.001), but not for SF-12 mental component (P=0.053). Patients with minimum 6 months radiographic follow-up demonstrated successful fusion in 90% of cases (35/39), with 2 cases of grade 1 (5%) subsidence of the adjacent cranial vertebra, and no cases higher than grade 0 subsidence of the adjacent caudal vertebra.

CONCLUSIONS: Unilateral pedicle screw instrumentation following LLIF was associated with significant improvement in clinical outcomes and favorable radiographic outcomes.