title: Are Locked Facets a Contraindication for Extreme Lateral Interbody Fusion?
abstract: BACKGROUND
  Extreme lateral interbody fusion (ELIF) has gained popularity as a minimally invasive treatment allowing for indirect decompression of neural elements. However, evidence regarding the influence of facet degeneration (FD) and facet tropism (FT) toward indirect decompression is lacking. The aim of the study was to evaluate whether indirect decompression is impaired by FD and FT in patients undergoing ELIF.
  
  
  METHODS
  Thirty-seven patients undergoing ELIF were included in a retrospective study. Radiographic parameters including disk height, segmental disk angle, foraminal area, FD, FT, and clinical outcome parameters (Oswestry Disability Index and Visual Analog Scale) were measured preoperatively and postoperatively. FD and FT were correlated with radiographic and clinical outcome parameters in order to determine predictors restricting indirect decompression.
  
  
  RESULTS
  Thirty-seven patients with a total of 74 levels were analyzed. Clinical and radiographic outcome measures including central canal area (Δ = +17.2 mm2), mean disk height (Δ = +3 mm), and foraminal area (Δ = +9.9 mm2) revealed significant improvement compared with before surgery (P ≤ 0.05). Patients with severe FD (grade 4) were more likely to have FT ≥ 12 degrees (32.3%) than patients without/mild (grades 0 and 1; 10%) or moderate FD (grades 2 and 3; 13%), P ≤ 0.05. FD and FT did not affect disk height restoration, foraminal area, canal surface area, or clinical outcome measures (P ≥ 0.05).
  
  
  CONCLUSIONS
  Indirect decompression of neural elements in ELIF is not impaired by FD and FT are not relative contraindications in patients undergoing ELIF.
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Navarro-Ramirez
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA; Department of Orthopedic and Trauma Surgery, Freiburg University Medical Center, Freiburg, Germany.
authors.forename: Gernot
authors.initials: G
authors.lastname: Lang
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Yu
authors.initials: Y
authors.lastname: Moriguchi
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Elowitz
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Jose Alfredo
authors.initials: JA
authors.lastname: Corredor
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Mauricio J
authors.initials: MJ
authors.lastname: Avila
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Alberto
authors.initials: A
authors.lastname: Gotfryd
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Marjan
authors.initials: M
authors.lastname: Alimi
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA.
authors.forename: Lena
authors.initials: L
authors.lastname: Gandevia
authors.affiliation: Weill Cornell Brain and Spine Center, Department of Neurological Surgery, Weill Cornell Medicine, New York-Presbyterian Hospital, New York, New York, USA. Electronic address: roger@hartlmd.net.
authors.forename: Roger
authors.initials: R
authors.lastname: Härtl
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000075202:Contraindications; D019299:Decompression, Surgical / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013123:Spinal Fusion; D013130:Spinal Stenosis / Q000000981:diagnostic imaging* / Q000601:surgery*; D016896:Treatment Outcome; D021801:Zygapophyseal Joint / Q000002:abnormalities* / Q000000981:diagnostic imaging / Q000601:surgery*
keywords: Degenerative; Facet degeneration; Facet tropism; Minimally invasive; Neural decompression; XLIF