title: MIS lateral spine surgery: a systematic literature review of complications, outcomes, and economics.
abstract: BACKGROUND
  Over the past decade, the minimally disruptive lateral transpsoas approach for lumbar interbody fusion (MI-LIF) is increasingly being used as an alternative to conventional surgical approaches. The purpose of this review was to evaluate four primary questions as they relate to MI-LIF: (1) Is there an anatomical justification for MI-LIF at L4-5? (2) What are the complication and outcome profiles of MI-LIF and are they acceptable with respect to conventional approaches? (3) Given technical and neuromonitoring differences between various MI-LIF procedures, are there any published clinical differences? And, (4) are modern minimally disruptive procedures (e.g., MI-LIF) economically viable?
  
  
  METHODS
  Through a MEDLINE and Google Scholar search, a total of 237 articles that discussed MI-LIF were identified. Of those, topical areas included anatomy (22), biomechanics/testing (17), technical descriptions (11), case reports (40), complications (30), clinical and radiographic outcomes (43), deformity (23), trauma or thoracic applications (10), and review articles (41).
  
  
  RESULTS
  In answer to the questions posed, (1) there is a high strength of evidence showing MI-LIF to be anatomically justified at all levels of the lumbar spine from L1-2 to L4-5. The evidence also supports the use of advanced neuromonitoring modalities. (2) There is moderate strength evidence in support of reproducible and reasonable complication, side effect, and outcome profiles following MI-LIF which may be technique dependent. (3) There is low-strength evidence that shows elevated neural complication rates in non-traditional (e.g., shallow-docking approaches and/or those without specialized neuromonitoring) MI-LIF, and (4) there is low- to moderate-strength evidence that modern minimally disruptive surgical approaches are cost-effective.
  
  
  CONCLUSIONS
  There is considerable published evidence to support MI-LIF in spinal fusion and advanced applications, though the results of some reports, especially concerning complications, vary greatly depending on technique and instrumentation used. Additional cost-effectiveness analyses would assist in fully understanding the long-term implications of MI-LIF.
authors: Spine Midwest, Inc., 200 St. Mary's Plaza, Suite 301, Jefferson City, MO, 65101, USA, jlehmenmd@gmail.com.
authors: Jeff A
authors: JA
authors: Lehmen
authors: Edward J
authors: EJ
authors: Gerber
mesh_terms: D003362:Cost-Benefit Analysis; D006801:Humans; D008159:Lumbar Vertebrae / Q000601:surgery*; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000191:economics; D063868:Patient Outcome Assessment; D013123:Spinal Fusion / Q000009:adverse effects* / Q000379:methods*