====== Minimally invasive lateral retroperitoneal transpsoas interbody fusion ======

[[Transpsoas approach]] and [[tubular retractor]] placement is achieved using sequential tubular dilators that are placed under the guidance of fluoroscopic imaging (or [[navigation]]) and using directional EMG monitoring ([[Neurovision]]TM, [[NuVasive]], San Diego, CA) allowing the dilator placed anterior to the main lumbar plexus.

A variety of surgical approaches have been described to treat low grade lumbar degenerative [[spondylolisthesis]] (DS). [[Minimally invasive]] spinal fusion techniques were first introduced to minimize morbidities associated with invasive surgical treatments. Minimally invasive [[lateral transpsoas interbody fusion]], also known as [[lateral lumbar interbody fusion]] ([[LLIF]]).
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Minimally invasive [[lateral retroperitoneal transpsoas interbody fusion]] was first introduced by Luiz Pimenta in [[2001]] 
((Pimenta L. Lateral endoscopic transpsoas retroperitoneal approach for lumbar spine surgery. Belo Horizo te, Minas Gerais, Brazil 2001))
((Ozgur BM, Aryan HE, Pimenta L, Taylor WR. Extreme Lateral Interbody Fusion (XLIF): a novel surgical technique for anterior lumbar interbody fusion. Spine J. 2006; 6:435–443)),
as an adaptation of an endoscopic lateral [[transpsoas approach]] to [[lumbar fusion]] described by Bergey et al. 
((Bergey DL, Villavicencio AT, Goldstein T, Regan JJ. Endoscopic lateral transpsoas approach to the lum- bar spine. Spine (Phila Pa 1976). 2004; 29:1681– 1688))

Trademarked names include “extreme-lateral” ([[XLIF]]TM, [[NuVasive]], San Diego, CA) or “direct-lateral” lumbar interbody fusion ([[DLIF]]TM, [[Medtronic]], Memphis, TN); the generic term [[lateral lumbar interbody fusion]] ([[LLIF]]) will be used here. Variants to the approach include the [[oblique lumbar interbody fusion]] ([[OLIF]]TM, Medtronic, Memphis, TN) which utilizes a pre-psoas approach (at L5-S1 the [[OLIF]] is halfway between an [[ALIF]] and a [[LLIF]]). A retroperitoneal approach. Indirectly decompresses nerves by distracting the disc space and fuses the spine with an [[interbody cage]] having a large cross-sectional area. Access is best from L1–5. For L1–2, one can retract the 12th rib, or go between 11th & 12th rib, or excise the 12th rib. [[Iliac crest]] prevents access to L5-S1 (axial-LIF may be used here) and occasionally to L4–5

A similar retro- pleural approach may be employed in the thoracic spine up to T4.  With thoracic lateral interbody fusions, DO NOT penetrate the contralateral anulus. Intra-operative EMG monitoring is critical, so the anesthesiologist needs to use only short-acting neuromuscular blockade at beginning of case. In males, implants are typically 55-60 mm in length (oriented along patient’s lateral axis) if placed in the midposition of the VB, or 45 mm in the anterior portion (lengths are 10%shorter in females)
((Hall LT, Esses SI, Noble PC, Kamaric E. Morphology of the lumbar vertebral endplates. Spine. 1998; 23:1517–22; discussion 1522-3
)).

Potential advantages include less tissue trauma, minimal blood loss, shorter operation time, less wound issues, placement of a larger cage, early patient mobilization
((Rodgers WB, Gerber EJ, Patterson J. Intraoperative and early postoperative complications in extreme lateral interbody fusion: an analysis of 600 cases. Spine (Phila Pa 1976). 2011; 36:26–32))
((Dakwar E, Cardona RF, Smith DA, Uribe JS. Early outcomes and safety of the minimally invasive, lat- eral retroperitoneal transpsoas approach for adult degenerative scoliosis. Neurosurg Focus. 2010; 28. DOI: 10.3171/2010.1.FOCUS09282))
, no risk of durotomy with CSF leak.

===== Robotic-guided prone transpsoas approach =====
[[Robotic-guided prone transpsoas approach]]