title: A novel minimally invasive technique for the treatment of high-grade isthmic spondylolisthesis using a posterior transsacral rod.
abstract: METHODS
  Case report of 3 patients with high-grade isthmic spondylolisthesis treated using a novel minimally invasive technique using a posterior transsacral rod.
  
  
  OBJECTIVE
  To assess the efficacy, safety, and advantages of this approach in the treatment of high-grade L5-S1 spondylolisthesis.
  
  
  BACKGROUND
  Surgical treatment of high-grade isthmic spondylolisthesis at the L5-S1 level is technically demanding. The most commonly used procedure is posterior spinal fusion. In this report, we present a new minimally invasive technique for the treatment high-grade isthmic spondylolisthesis in 3 patients with sagittally balanced spines.
  
  
  METHODS
  Three patients with high-grade L5-S1 spondylolisthesis underwent L4-S1 fusion with percutaneous pedicle screw fixation supplemented with a transsacral rod implanted through a tubular retractor. We report technical details, clinical, and radiologic results at follow-up.
  
  
  RESULTS
  All 3 patients suffered from grade 3 or 4 L5-S1 spondylolisthesis. All patients had neutral sagittal balance on preoperative imaging. There were no postoperative complications and all 3 patients were discharged within 48 hours. At final follow-up (range, 13-18 mo), all patients were pain free off all narcotic pain medication and fusion was observed in all 3 patients.
  
  
  CONCLUSIONS
  We have shown the technical feasibility of anterior and posterior fusion for severe L5-S1 spondylolisthesis using a minimally invasive percutaneous technique through a transsacral approach. The main advantage of a posterior transsacral axial rod fixation is that it creates a structurally sound anterior column support, thus eliminating the problems related to bone grafts and eliminating the complications associated with an anterior approach. Our preliminary results suggest that this technique is feasible and seems to be associated with favorable outcome, although larger studies are warranted to verify these findings.
authors.affiliation: *Division of Neurosurgery, Hôpital Notre-Dame du CHUM, University of Montreal, Montreal, QC, Canada †Texas Health Resource Hospital, Plano, TX.
authors.forename: Daniel
authors.initials: D
authors.lastname: Shedid
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Weil
authors.forename: Isidore
authors.initials: I
authors.lastname: Lieberman
mesh_terms: D000328:Adult; D001863:Bone Screws; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000000981:diagnostic imaging / Q000601:surgery; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D011183:Postoperative Complications / Q000209:etiology; D011859:Radiography; D012447:Sacrum / Q000601:surgery*; D013168:Spondylolisthesis / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome