Ilioinguinal Approach to Acetabulum indications:

The ilioinguinal approach to acetabulum allows exposure of the inner surface of the pelvis from the sacroiliac joint to the pubic symphysis. It allows visualization of the anterior and medial surfaces of the acetabulum, it’s suitable for exposure of anterior column fractures of the acetabulum.

The ilioinguinal approach to acetabulum is used for:

  1. Anterior wall fractures.
  2. Anterior column fractures.
  3. Anterior column plus posterior hemi-tranverse fractures.
  4. Open reduction and internal fixation of most both-column fractures.
  5. Some T-type.
  6. Some transverse fractures type.
  7. For transverse fractures if displacement is anterior.
See Also: Pelvic Fractures

Position of the Patient

  • Place the patient supine on the operating table with greater troch on side of fracture at edge of table.
  • Place bump under ipsilateral buttock.
  • Flex affected leg to relax iliopsoas and neurovascular structures.

Landmarks and Incision

Landmarks:

  1. The anterior superior iliac spine.
  2. Pubic Tubercles.

Incision:

  • Make a curved anterior incision beginning 5 cm above the anterior superior iliac spine.
  • Extend the incision medially, passing 1 cm above the pubic tubercle to end in the midline.
Ilioinguinal Approach to Acetabulum

Internervous plane

  • There is no true internervous plane for the The ilioinguinal approach to acetabulum.
  • The dissection consists essentially of lifting off muscular, nervous, and vascular structures from the inner wall of the pelvis.

Superficial dissection

Ilioinguinal Approach to Acetabulum superficial dissection is carried out as following:

  • Dissect down through the subcutaneous fat to expose the aponeuroses of the external oblique muscle.
  • Divide the aponeurosis of the external oblique muscle in the line of its fibers from the superficial inguinal ring to the
    anterior superior iliac spine (This will expose the spermatic cord in the male and the round ligament in the female).
  • Carefully isolate these structures in a sling.
  • Continue the dissection medially, dividing the anterior part of the rectus sheath to expose the underlying rectus abdominis muscle.
  • Strip the iliacus muscle from the inside of the wing of the ilium. Initially, you will need to use sharp dissection, but once inside the pelvis, use blunt dissection.

Deep dissection

Ilioinguinal Approach to Acetabulum deep dissection is carried out as following:

  • Bluntly dissect a plane between the symphysis pubis and the bladder (space of Retzius), pack with sponges,
  • Expose anterior aspect of femoral vessels and surrounding lymphatics in midportion of incision (lacuna vasorum):
    • Lacuna musculorum is lateral and contains iliopsoas, femoral nerve, and lateral femoral cutaneous nerve.
  • Identify iliopectineal fascia, which separates the lacuna vasorum and lacuna musculorum.
  • Dissect vessels and lymphatics from medial aspect of fascia, free iliopsoas and femoral nerve from lateral aspcet of fascia.
  • Sharply divide iliopectineal fascia down to pectineal eminence, then detach from pelvic brim; allows access to true pelvis, quadrilateral plate, and posterior column.
  • Place second penrose drain around iliopsoas, femoral nerve, and lateral femoral cutaneous nerve.
  • Place thrid penrose drain around femoral vessels and lymphatics.
  • Identify and ligate corona mortise before retracting vessels.
  • Subperiosteal dissection is used to expose pelvic brim, rami, and quadrilateral surface.

Work through 3 windows to reduce and fix fracture:

  1. Medial window:
    • Medial to external iliac artery and vein.
    • Access to pubic rami; indirect access to internal iliac fossa and anterior SI joint.
  2. Middle window:
    • Between external iliac vessels and the iliopsosas muscle.
    • Access to pelvic brim, quadrilateral plate, and a portion of the superior pubic ramus.
  3. Lateral window:
    • Lateral to iliopsoas (iliopectineal fascia).
    • Access to quadrilateral plate, SI joint, and iliac wing.

Approach Extension

Proximal Extension:

  • The ilioinguinal approach to acetabulum can be extended proximally to expose the sacroiliac joint.
  • Extend the skin incision posteriorly, following the iliac crest.
  • Using sharp dissection, cut down onto the bone.
  • Then strip off the origins of the iliacus from the inside of the ilium using blunt dissection.
  • Retract this iliacus medially to expose the inner wall of the ilium and the sacroiliac joint.

Distal Extension:

  • Ilioinguinal approach to acetabulum cannot be extended distally.

Dangers

The structures at risk during ilioinguinal approach to acetabulum include:

  1. Femoral nerve.
  2. Femoral and External Iliac Arteries:
    • Damage can cause thrombosis.
    • Protect them by leaving in femoral sheath.
  3. Lymphatics:
    • Present in fatty areolar tissue around vessels.
    • Disruption can impair postoperative lymphatic drainage and cause edema.
  4. Lateral cutaneous nerve of thigh:
    • Often have to sacrifice leaving numbness on the outer side of the thigh.
  5. Inferior epigastic artery:
    • Must sacrifice if has anomoulous origin off obturator artery to allow retraction of iliac vessels.
  6. Spermatic cord (contains vas deferens and testicular artery):
    • Must be protected.
    • Damage can cause testicular ischemia, infertility.
  7. Heterotopic Ossification:
    • Much more common in the extended iliofemoral and Kocher-Lagenbeck approaches.
  8. Obturator nerve:
    • Causes medial thigh numbness when injured.

References

  • Surgical Exposures in Orthopaedics book – 4th Edition
  • Campbel’s Operative Orthopaedics book 12th