title: Presacral retroperitoneal approach to axial lumbar interbody fusion: a new, minimally invasive technique at L5-S1: Clinical outcomes, complications, and fusion rates in 50 patients at 1-year follow-up.
abstract: BACKGROUND
  The presacral retroperitoneal approach to an axial lumbar interbody fusion (ALIF) is a percutaneous, minimally invasive technique for interbody fusion at L5-S1 that has not been extensively studied, particularly with respect to long-term outcomes.
  
  
  OBJECTIVE
  The authors describe clinical and radiographic outcomes at 1-year follow-up for 50 consecutive patients who underwent the presacral ALIF.
  
  
  METHODS
  Our patients included 24 males and 26 females who underwent the presacral ALIF procedure for interbody fusion at L5-S1. Indications included mechanical back pain and radiculopathy. Thirty-seven patients had disc degeneration at L5-S1, 7 had previously undergone a discectomy, and 6 had spondylolisthesis. A 2-level L4-S1 fusion was performed with a transforaminal lumbar interbody fusion at L4-5 in 15 patients. AxiaLIF was performed as a stand-alone procedure in 5 patients and supplemented with pedicle screws in 45 patients. Pre- and postoperative visual analog scale (VAS) and Oswestry Disability Index (ODI) scores were evaluated and complications were tracked. Fusion was evaluated by an independent neuro-radiologist.
  
  
  RESULTS
  At 1-year follow-up, VAS and ODI scores had significantly improved by 49% and 50%, respectively, versus preoperative scores. By high-resolution computer tomography (CT) scans, fusion was achieved in 44 (88%) patients, developing bone occurred in 5 (10%), and 1 (2%) patient had pseudoarthrosis. One patient suffered a major operative complication-a bowel perforation with a pre-sacral abscess that resolved with treatment.
  
  
  CONCLUSIONS
  Our initial 50 patients who underwent presacral ALIF showed clinical improvement and fusion rates comparable with other interbody fusion techniques; its safety was reflected by low complication rates. Its efficacy in future patients will continue to be monitored, and will be reported in a 2-year follow-up study of fusion.
authors: Department of Neurosurgery, University of Cincinnati (UC) Neuroscience Institute, UC College of Medicine, Mayfield Clinic and Spine Institute, and The Christ Hospital, Cincinnati, OH.
authors: Robert J
authors: RJ
authors: Bohinski
authors: Department of Orthopedic Surgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.
authors: Viral V
authors: VV
authors: Jain
authors: Department of Neurosurgery, University of Cincinnati (UC) Neuroscience Institute, UC College of Medicine, Mayfield Clinic and Spine Institute, and The Christ Hospital, Cincinnati, OH.
authors: William D
authors: WD
authors: Tobler
keywords: AxiaLIF; Interbody fusion; Minimally invasive fusion; Percutaneous fusion