title: A surgical option for multilevel anterior lumbar interbody fusion with ponte osteotomy to achieve optimal lumbar lordosis and sagittal balance.
abstract: OBJECTIVE
  To document lumbar lordosis (LL) of the spine and its change during surgeries with the different height but the same angle setting of the anterior cage. Additionally, we attempted to determine if sufficient LL is achieved at different cage heights and to quantify the change in LL during multi-level anterior lumbar interbody fusion (ALIF).
  
  
  METHODS
  The medical records and radiographs of 42 patients who underwent more than 2 level ALIFs between 2008 and 2009 were retrospectively reviewed. We evaluated 3 parameters seen on lateral whole spine radiographs : LL, pelvic incidence (PI), and sagittal vertical axis (SVA). The mean follow-up time was 28.1 months and the final follow-up radiographs of all patients were reviewed at least 2 years after surgery. Statistical analysis was performed using the paired t-tests.
  
  
  RESULTS
  Lumbar lordosis had changed up to 30 degrees immediately and 2 years after surgery (preoperative mean LL, SVA : 22.45 degrees, 112.31 mm; immediate postoperative mean LL, SVA : 54.45 degrees, 37.36 mm; final follow-up mean LL, SVA : 49.56 degrees, 26.95 mm). Our goal of LL is to obtain as much PI as possible, preoperative mean PI value was 55.38±3.35. The pre-operative and two year post-surgery follow-up mean of the Japanese Orthopedic Association score were 9.2±0.6 and 13.2±0.6 (favorable outcome rate : 95%), respectively. In addition, we were able to obtain good clinical outcomes and sagittal balance with a subsidence rate of 22.7%.
  
  
  CONCLUSIONS
  We were able to achieve sufficient LL, such that it was similar to the PI, utilizing multi-level ALIF with the use of a tall cage with the same angle setting of the cage. We have found out that achieving sufficient lumbar lordosis and sagittal balance require an anterior lumbar cage with high angle and height.
authors.affiliation: Spine Center, Kyung Hee University Hospital at Gangdong, Seoul, Korea.
authors.forename: Loo-Ree
authors.initials: LR
authors.lastname: Suh
authors.forename: Dae-Jean
authors.initials: DJ
authors.lastname: Jo
authors.forename: Sung-Min
authors.initials: SM
authors.lastname: Kim
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Lim
keywords: ALIF; Anterior interbody fusion; Anterior lumbar cage; Multilevel ALIF; Pelvic incidence; Sagittal balance