Anterior Smith-Petersen Approach to Hip

Anterior Smith-Petersen Approach to Hip, muscles of the front of the thigh
Muscles of the front of the thigh. Image by Henry Vandyke Carter, Wikimedia Commons, Public domain.

Indications

  • True internervous approach to the anterior hip and ilium
  • Open reduction of developmental dysplasia of the hip
  • Drainage of septic arthritis
  • Femoral head fractures, especially anterior Pipkin fragments
  • Salter osteotomy, periacetabular osteotomy and iliac crest graft harvest
  • Hemiarthroplasty and total hip replacement, with DAA using the distal interval

Position

  • Supine with a small bolster under the ipsilateral buttock

Landmarks and Incision

  • Landmarks are the iliac crest and ASIS
  • Incision along the anterior half of the crest to the ASIS, then distally towards the lateral patella

Internervous Plane

  • Superficial plane between sartorius (femoral nerve) and TFL (superior gluteal nerve)
  • Deep plane between rectus femoris (femoral nerve) and gluteus medius (superior gluteal nerve)

Superficial Dissection

  • LFCN pierces the fascia near the ASIS and runs over sartorius, so incise fascia on the tensor side
  • Develop the sartorius and TFL interval
  • Proximally elevate gluteus medius and TFL subperiosteally from the outer table
  • Ligate the ascending branch of the lateral femoral circumflex artery

Deep Dissection

  • Detach rectus femoris direct head from the AIIS and reflected head from the superior rim
  • Retract rectus and iliopsoas medially and gluteus medius laterally
  • T-shaped capsulotomy
  • Anterior dislocation with external rotation and adduction

Direct anterior approach

  • Distal Hueter interval through a shorter incision, with no muscle detached from the pelvis
  • Incision distal and lateral to the ASIS over the TFL belly
  • TFL retracted laterally within its sheath, keeping the LFCN medial
  • Neck osteotomy in situ, with fluoroscopy for cup position and leg length
  • Femoral exposure needs extension, adduction, external rotation and posterosuperior capsular release
  • Muscle sparing with a low dislocation rate
  • LFCN neurapraxia, femoral fracture or perforation, and wound problems in obese groin folds

Structures at Risk

  • LFCN, causing meralgia paraesthetica
  • Femoral nerve, medial to the approach
  • Ascending branch of the lateral femoral circumflex artery

Extension

  • Proximally along the crest into the iliofemoral approach to both iliac tables
  • Distally into the anterolateral approach to the femoral shaft

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