Anterolateral Retroperitoneal Approach

Incision planning and the retroperitoneal corridor for the oblique anterolateral approach at L2 to L5 (A, C, E) and at L5 to S1 (B, D, F)
Incision planning and the retroperitoneal corridor for the oblique anterolateral approach at L2 to L5 (A, C, E) and at L5 to S1 (B, D, F). The axial drawings show the peritoneal contents swept forward by blunt finger dissection to reach the disc. Image from Han J, Han S, Meng S, Zhao X, Zhang H, Guo J, Xu D, Liu H, Chen M, Ma X, Wang Y. Application of the oblique lateral interbody fusion technique in salvage surgery, technical note and case series. Front Surg. 2023, 10, 1144699. CC BY 4.0.
Anterolateral Retroperitoneal Approach, psoas major, gray’s anatomy plate 430
Psoas major, Gray’s Anatomy plate 430. Image by Henry Vandyke Carter, Wikimedia Commons, Public domain.

Indications

  • Access to L1 to Sacrum
  • Drainage of psoas abscess
  • Spinal fusion
    • Approach from Left because Aorta is harder to damage than IVC

Position

  • Semi lateral position at 45° facing away from surgeon
    • Sandbags under hips & shoulder
    • Allows peritoneal contents to fall away from incision
    • Tilt table

Landmarks

  • 12th rib
  • pubic symphysis
  • lateral border of rectus abdominis
    • 5cm lateral to midline

Incision

  • oblique flank incision extending from
  • Start: posterior half of the 12th rib towards the lateral border of rectus abdominis
  • End: Halfway between umbilicus & pubic symphysis

Internervous Plane

  • No true plane
    • External oblique, Internal oblique & Transversus abdominis are innervated segmentally

Superficial Dissection

  • Fat
  • Aponeurosis of external oblique muscle
  • Incise
    • External oblique
    • Internal oblique
    • Transversus abdominis
  • Exposes retroperitoneal space
  • Blunt finger dissection with finger
    • Develop plane between retroperitoneal fat & fascia overlying psoas muscle
  • Gently mobilise peritoneal cavity & retract medially using Dever retractor

Deep Dissection

  • identify Psoas fascia
    • genitofemoral nerve
    • segmental lumbar branches of aorta
    • sympathetic chain
  • Psoas Abscess
    • Locate abscess & drain
  • Fusion
    • Ligate & tie segmental lumbar branches of aorta & IVC

Dangers

  • Nerves
    • Sympathetic chain
    • Genitofemoral nerve
  • Vessels
    • Segmental lumbar arteries & veins
    • Vena Cava
    • Aorta
  • Ureter

Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 10 October 2026.