title: Minimally Invasive Transforaminal Lumbar Interbody Fusion Using Expandable Technology: A Clinical and Radiographic Analysis of 50 Patients.
abstract: OBJECTIVE
  Interbody cage implantation during minimally invasive surgery for transforaminal lumbar interbody fusion (MIS TLIF) presents challenges. Expandable cages when collapsed facilitate insertion; subsequent expansion in situ optimizes endplate contact. This report describes clinical and radiographic outcomes of MIS TLIF with an expandable cage.
  
  
  METHODS
  Researchers retrospectively analyzed prospective data from 50 patients (62 operative levels) when an expandable interbody spacer was combined with transpedicular posterior stabilization. Clinical outcomes, fusion rates, incidence of reoperation, and device-related complications were obtained from clinical and radiographic records.
  
  
  RESULTS
  Mean patient age was 58.1 years (56.2% female). In all, 76% (38/50) underwent 1-level fusion, and 24% (12/50) 2-level fusion. Average operative time was 239.9 ± 86.9 minutes for 1-level and 350.3 ± 74.9 minutes for 2-level procedures; average hospital stay overall was 2.5 ± 1.7 days, with no intraoperative complications reported. Mean visual analogue scale and Oswestry Disability Index scores decreased significantly from preoperative to all postoperative assessment times (6, 12, and 24 months) (P < 0.05). Intervertebral disc height (8.3 ± 2.7 vs. 11.3 ± 1.9 mm) increased significantly, with increases sustained over 24 months (P < 0.05). Postoperative radiographs showed no evidence of cage migration, subsidence, or collapse and suggested fusion at all operative levels by 12 months and 24 months (93%, 54/58; 97%, 28/29), respectively.
  
  
  CONCLUSIONS
  An expandable interbody cage led to significant improvement in clinical and radiographic outcomes after MIS TLIF, including intervertebral disc height restoration and high fusion rates, with no evidence of device-related complications.
authors.affiliation: Spine Institute of San Diego, Center for Minimally Invasive Spine Surgery at Alvarado Hospital, San Diego, California, USA. Electronic address: ck11@chollkim.com.
authors.forename: Choll W
authors.initials: CW
authors.lastname: Kim
authors.affiliation: Spine & Orthopedic Specialists, Scottsdale, Arizona, USA.
authors.forename: Todd M
authors.initials: TM
authors.lastname: Doerr
authors.affiliation: Musculoskeletal Education and Research Center (MERC), A Division of Globus Medical, Inc., Audubon, Pennsylvania, USA.
authors.forename: Ingrid Y
authors.initials: IY
authors.lastname: Luna
authors.affiliation: Musculoskeletal Education and Research Center (MERC), A Division of Globus Medical, Inc., Audubon, Pennsylvania, USA.
authors.forename: Gita
authors.initials: G
authors.lastname: Joshua
authors.affiliation: Department of Spinal Surgery, Second Affiliated Hospital of Wenzhou Medical University, Zhejiang Spinal Research Center, Wenzhou, Zhejiang Province, People's Republic of China.
authors.forename: Sun Ren
authors.initials: SR
authors.lastname: Shen
authors.affiliation: Tianjin Hospital, Tianjin, People's Republic of China.
authors.forename: Xin
authors.initials: X
authors.lastname: Fu
authors.affiliation: Department of Spinal Surgery, Second Affiliated Hospital of Wenzhou Medical University, Zhejiang Spinal Research Center, Wenzhou, Zhejiang Province, People's Republic of China.
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Wu
mesh_terms: D055119:Elastic Modulus; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D017116:Low Back Pain / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery*; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D010147:Pain Measurement; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology / Q000517:prevention & control*; D011474:Prosthesis Design; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000009:adverse effects / Q000295:instrumentation* / Q000379:methods; D016896:Treatment Outcome; D014481:United States
keywords: Degenerative disc disease; Expandable interbody spacer; Interbody fusion; MIS TLIF; Stenosis