title: Posterolateral fusion with interbody for lumbar spondylolisthesis is associated with less repeat surgery than posterolateral fusion alone.
abstract: OBJECTIVE
  Posterior or transforaminal lumbar interbody fusions (PLIF/TLIF) may improve the outcomes in patients with lumbar spondylolisthesis. This study aims to compare outcomes after posterolateral fusion (PLF) only versus PLF with interbody fusion (PLF+PLIF/TLIF) in patients with spondylolisthesis.
  
  
  METHODS
  We retrospectively reviewed103 patients who underwent first-time instrumented lumbar fusions for degenerative or isthmic spondylolisthesis. Anterior techniques and multilevel interbody fusions were excluded. All patients were followed for at least 2 years postoperatively. Clinical outcomes including back pain, radiculopathy, weakness, sensory deficits, and loss of bowel/bladder function were ascertained from clinic notes. Radiographic measures were calculated with Tillard percentage of spondylolisthesis. Reoperation for progression of degenerative disease, a primary endpoint, was indicated for all patients with (1) persistent or new-onset neurological symptoms; and (2) radiographic imaging that correlated with clinical presentation.
  
  
  RESULTS
  Of the 103 patients, 56.31% were managed with PLF and 43.69% with PLF+PLIF/TLIF. On radiographic studies, spondylolisthesis improved by a mean of 13.06% after PLF+PLIF/TLIF versus 5.67% after PLF (p<0.001). In comparison to PLF+PLIF/TLIF, patients undergoing PLF experienced higher rates of postoperative improvement in back pain, sensory deficits, motor weakness, radiculopathy, and bowel/bladder difficulty; however, these differences did not reach statistical significance. The PLF cohort had a significantly higher incidence of reoperation (p=0.011) and pseudoarthrosis/instrumentation failure (p=0.043). In the logistical analyses, non-interbody fusion was the strongest predictor of reoperation for progression of degenerative disease.
  
  
  CONCLUSIONS
  Compared to PLF only, PLF+PLIF/TLIF were statistically significantly associated with a greater correction of spondylolisthesis. Patients with interbody fusions were less likely to undergo reoperation for degenerative disease progression compared to non-interbody fusions. However, greater listhesis correction and decreased reoperation in the PLF+PLIF/TLIF cohort should be weighed with favorable clinical outcomes in the PLF cohort.
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America; Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, MD, United States of America.
authors: Mohamed
authors: M
authors: Macki
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America; Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, MD, United States of America.
authors: Mohamad
authors: M
authors: Bydon
authors: Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, MD, United States of America.
authors: Robby
authors: R
authors: Weingart
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.
authors: Daniel
authors: D
authors: Sciubba
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America.
authors: Jean-Paul
authors: JP
authors: Wolinsky
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America; Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, MD, United States of America.
authors: Ziya L
authors: ZL
authors: Gokaslan
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America; Johns Hopkins Spinal Biomechanics and Surgical Outcomes Laboratory, Baltimore, MD, United States of America.
authors: Ali
authors: A
authors: Bydon
authors: Department of Neurosurgery, Johns Hopkins University School of Medicine, Baltimore, MD, United States of America. Electronic address: twitham2@jhmi.edu.
authors: Timothy
authors: T
authors: Witham
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D016268:Internal Fixators; D017116:Low Back Pain / Q000209:etiology; D008159:Lumbar Vertebrae / Q000601:surgery*; D008161:Lumbosacral Region / Q000601:surgery; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D012086:Reoperation; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000379:methods*; D013168:Spondylolisthesis / Q000145:classification / Q000601:surgery*; D016896:Treatment Outcome
keywords: Interbody; Lumbar; PLIF; Posterolateral fusion; Spondylolisthesis; TLIF