Surgical Approaches to Acetabulum

Last Updated on November 22, 2023

Approaches to Acetabulum

Approaches to acetabulum could be anterior approaches, posterior approaches or extensile approaches.

Anterior approaches to acetabulum include

• Iliofemoral Approach
• Ilioinguinal Approach

Posterior approaches to acetabulum include

• Kocher Langenbach
• Transtroachanteric

Extensile approaches to acetabulum include

• Triradiate Transtrochanteric
• Extended Iliofemoral

Iliofemoral Apporach to Acetabulum

This approach provides access to the iliac crest and the entire internal iliac fossa and visualization of the anterior aspect of the sacroiliac joint, if needed.

With this incision, the surgeon cannot gain access to the anterior column distal to the iliopectoral eminence, but in many cases this is not needed. Increased exposure may be obtained by adduction and internal rotation of the hips.

Access to the quadrilateral surface and greater sciatic notch are limited.

Indications

• Anterior column  fractures
• Anterior wall fractures
• Aanterior column  with posterior hemitransverse  fractures [Posterior  hemitransverse segment is often undisplaced.]

The best candidates for this approach are those where the fracture pattern extends to the crest and there is a single large anterior column component.

Approach Details

• The proximal end of the skin incision parallels the iliac crest and begins posterior to the gluteus medius pillar. [Skin incision relative to the crest may need to be modified depending on the body habitus of the patient.]
• Extension to the anterior superior iliac spine [ or 1-2 cm lateral to the anterior superior iliac spine], and then continued distally along the interval between the sartorius and tensor muscle o r over the anterior aspect of the tensor muscle belly.
• External oblique muscle is released from the crest after superficial dissection. A thick fascial/periosteal cuff is left to facilitate subsequent repair.
• In continuity with the release of the external oblique
• In some cases it is possible to facilitate the deep exposure by osteotomizing the anterior superior iliac spine.
• When the fracture pattern does not permit osteotomy[ i.e. – fractures which encroach on the area of the osteotomy. the distal interval remains the same, and the deep exposure is provided by sharp release of the sartorius origin and inguinal ligament from the anterior superior iliac spine.
• Distal exposure starts1-2 cm lateral to the anterior superior iliac spine, the superficial and deep fascia of the thigh are incised extending distally and laterally over the tensor muscle belly.The interval is between tensor fascia lata [retracted laterally ] and sartorius [retracted medially]. The incision is extended distally at least 12-15 cm for the typical exposure.
• The further deep dissection proceeds through the floor of the tensor sheath.Distally, approximately 10 cm from the anterior superior iliac spine, the ascending branches of the lateral femoral circumflex artery and vein are encountered under the thick aponeurotic fascial layer over the rectus femoris muscle. In some cases it may be necessary to ligate or cauterize these vessels to optimize the distal exposure.

• Hip flexion and adduction to reduce the tension on the iliopsoas and aid in visualization
• The iliopectineal fascia is released from the pelvic brim starting just anterior to the SI joint and extending anteriorly to the level of the pubic root. This portion of the dissection allows access to the true pelvis. This access can be further developed by subperiosteal elevation of the obturator internus from the quadrilateral surface. The path of the obturator neurovascular bundle must be protected with careful medial retraction.
• Arthrotomy
  • The hip is positioned in approximately 20 degrees flexion.
  • The proximal rectus femoris and subjacent capsular portion of the iliacus are sharply elevated from the anterior hip capsule and retracted .
  • A T-shaped arthrotomy is then carried out.
• Wound closure
• Begin with loose repair of the capsule
• Deep drains are placed.
• The external oblique is repaired to the iliac crest.  T
• If osteotomized, anterior superior iliac supine block bone block is reattached with 2.7 or 3.5 mm lag screws.
• The distal portion of the deep wound is repaired at the superficial fascial layer.
• Subcutaneous drains are inserted, followed by subcutaneous and skin closure.

 

Ilioinguinal Approach

The ilioinguinal approach was developed by Emile Letournel to provide anterior access for fractures of the acetabulum.

It allows exposure to

• Entire internal iliac fossa and pelvic brim from the SI joint to the pubic symphysis
• Quadrilateral surface of innominate bone and superior/inferior pubic rami (thus allows exposure of anterior column)
• Portion of external aspect of ilium

The posterior column may be approached  anteriorly  by exposing the quadrilateral  plate.

Articular surfaces are done indirectly by restoration of extraarticular anatomy as the joint can not be directly visualized with this approach.

Indications

The ilioinguinal approach is used for virtually all fractures of the anterior wall and anterior column as well as associated anterior plus posterior hemi-transverse patterns.

Majority of both column fractures can be operated using the ilioinguinal approach.

An occasional transverse or T-shape fracture may be treated using this approach.

The ilioinguinal  approach  is ideal for difficult fractures with anterior displacement where access to the whole anterior column  is essential. Some both-column fractures are also amenable to this approach, mainly those fractures with a large single fragment of posterior  column.

Specific indications are

• Anterior wall fractures
• Anterior column fractures
• Anterior column plus posterior hemitranverse fractures
• Majority of associated both-column fractures
  • not recommended for fractures associated with comminuted post wall fractures or SI joint fractures
• Some T-type fractures
  • can used for minimally posteriorly displaced T-type fractures
• Few transverse type fractures

Approach Details

• Incision begins at midline 3-4cm proximal to symphysis pubis, proceeds laterally to anterosuperior iliac spine, then along anterior 2/3’s of iliac crest. The incision is extended beyond most convex portion of ilium.
• Superficial dissection
  •  It is through subcutaneous fat and periosteum is incised along iliac crest.
  • Abdominal and iliacus muscle insertions are raised from ilium to bare internal iliac fossa till SI joint and pelvic brim. Internal iliac fossa is packed for hemostasis.
  • Expose and divide aponeurosis of external oblique and rectus abdominus in line with skin incision one cm proximal to external inguinal ring. Often the  lateral cutaneous nerve of the thigh needs to be sacrificed.
  • This  unroofs inguinal canal, and exposes inguinal ligament. Ilioinguinal  nerve, isolate spermatic cord/round ligament are identified and protected.
  • Inguinal ligament is divided leaving 1-2mm cuff of ligament still attached to origin of abdominals.
  • May need to divide conjoint tendon at its insertion on pubis as well as anterior rectus sheath.
• Deep Dissection
  • Bluntly dissect a plane between the symphysis pubis and the bladder, pack with sponges
  • Expose anterior aspect of femoral vessels and surrounding lymphatics in midportion of incision. It is called lacuna vasorum. Lacuna musculorum is lateral and contains iliopsoas, femoral nerve, and lateral femoral cutaneous nerve. Iliopectineal fascia seperates the lacuna vasorum and lacuna musculorum
  • Isolate and protect vessels,  free iliopsoas and femoral nerve  and sharply divide iliopectineal fascia down to pectineal eminence.
  • Detach the fascia from pelvic brim. This allows access to true pelvis, quadrilateral plate, and posterior column
  • Corona mortise refers to retropubic vascular communication between either the external iliac (or deep epigastric vessels) and the obturator artery. It should be identified and ligated before vessels are ligated.
  • Continue subperiosteal dissection is to expose pelvic brim, rami, and quadrilateral surface

With this approach, following working windows are available

• Medial window
  • medial to external iliac artery & vein
  • access to pubic rami; indirect access to internal iliac fossa and anterior SI joint
• Middle window
  • between external iliac vessels and the iliopsosas
  • access to pelvic brim, quadrilateral plate, and a portion of the superior pubic ramus
• Lateral window
  • lateral to iliopsoas (iliopectineal fascia)
  • access to quadrilateral plate, SI joint, and iliac wing

After the procedure is completed suction drains are placed, conjoint tendon of abdominal muscles repaired and repair tendon of rectus abdominus and roof of inguinal canal is repaired by closure of aponeurosis of external oblique

The following structures are at risk with this approach

• Femoral nerve
• Femoral & External Iliac Arteries
• Lymphatics
• Lateral cutaneous nerve of thigh
• Inferior epigastic artery
• Spermatic cord (
• Obturator nerve

 

Kocher-Langenbeck Approach

This approach is used in acetabular fractures such as isolated posterior lip injuries and in posterior column injuries, either  isolated or associated with a posterior  lip

Southern/Moore approach  which is used for limited hip exposure uses the same interval as Kocher-Langenbeck.

This approach provides exposure to

• • Posterior wall of acetabulum
  • Lateral aspect of the posterior column of acetabulum
  • Proximal femur

It provides indirect access to true pelvis and anterior aspect of posterior column through palpation

 

Indications

• • Hip arthroplasty
  • Removal of loose bodies
  • Dependent drainage of septic hip
  • Pedicle bone grafting
  • posterior wall and posterior column fractures

Approach Details

Longitudinal incision centered over greater trochanter is made starting  below iliac crest, lateral to PSIS and extends to 10 cm below tip of greater trochanter

• Superficial dissection
  • The obturator internus should be tagged 1.5 cm from the greater trochanter and blunt dissection should be used to follow its origin to the lesser sciatic notch
    • Posterior retraction will protect the sciatic nerve
  • After dissecting subcutaneous fat, an incision is made in fascia lata in lower half of incision and extended  proximally along anterior border of gluteus maximus
  • Gluteus maximus muscle is split along avascular plane
  • Short external rotators are tagged and released. Release of piriformis muscle should be  1.5cm from the tip of the greater trochanter to avoid damaging the blood supply to the femoral head
  • The piriformis will provide a landmark leading to the greater sciatic notch. It is one of the contents  of the greater along with superior and inferior gluteal vessels and nerves, sciatic and posterior femoral cutaneous nerves, internal pudendal vessels and nerves to the obturator internus and quadratus femoris
  • Clear abductors and soft tissue to visualize posterior capsule and posterior wall region
• Deep dissection
  • Further dissection is not required in case of isolated fracture of posterior wall
  • Exposure of quadrilateral plate is done by the elevation of obturator internus  and release of sacrospinous ligament
  • For exposing hip joint, marginal capsulotomy is done and visualization of intra-articular surface of hip joint is aided by traction of femur
  • For extension of access to external surface of anterior column osteotomy of greater trochanter is done.

Following structures are at risk in this approach

• Sciatic nerve
• Inferior gluteal artery
• First perforating branch of profunda femoris
• Femoral vessels
• Superior gluteal artery and nerve
• Quadratus femoris

Posterior  Transtrochanteric Approach

For   difficult   injuries  involving the  dome  of the  acetabulum,  such as the  transverse T types with or  without  a posterior lip component , along with Kocher-Langenbeck skin incision, greater trochanter can be removed. The approach  through  the  gluteus maximus  and  tensor  fascia lata  muscles  is the same, and the piriformis muscle and external rotators are divided to expose the posterior  column as previously described. Removal of the greater trochanter greatly simplifies the opereative procedure.

The trochanter  is removed transversely and retracted superiorly. The plane between the hip joint capsule and the gluteus minimus  muscle is developed. Excellent exposure of the dome and posterior  column is obtained  with this approach.  Further exposure of the anterior aspect of the joint is made possible by dissection anteriorly to expose the anterior inferior spine and the rectus femoris muscle. Removal of the rectus  femoris will allow the surgeon  to examine the anterior column of the acetabulum. If necessary, fixation of the anterior column will require  retro- grade lag screws.

Triradiate Transtrochanteric

The approach is extension of Posterior  Transtrochanteric approach. This approach is useful in type C  both-column fractures with major posterior  displacement.  The approach includes  a posterolateral incision is made as in Transtrochanteric approach and  the same deep dissection carried out, and the trochanter  removed.

The  access to the iliac crest is essential, so the incision  is carried  anteriorly  in a triradiate fashion to the anterior  superior  spine or just distal to .

The tensor  fasciae latae muscle is divided, exposing the gluteus medius and minimus muscles, which are dissected subperiosteally from the outer table of the ilium.

The incision may be carried posteriorly along the iliac crest. The addition  of the triradiate skin incision and the subperiosteal dissec- tion posteriorly allows excellent visualization of the outer  table  of the  ilium, so essential  in the  both- column fracture.

The triradiate approach may also expose the inner aspect of the pelvis by extending the anterior  limb of the incision to the symphysis, converting  it into an ilioinguinal approach. This approach is truly extensile, since it allows exposure of both the outer  and inner  tables of the ilium, including  both columns.

Sciatic nerve, gluteal vessels and gluteal nerve are at risk.

Extended Iliofemoral Approach

The extended iliofemoral approach  gives excellent visualization  of the outer table of the ilium, the superior dome, and the posterior column, and may be further extended to include the inner wall of the ilium as well

The extended iliofemoral approach exposes the entire lateral innominate bone, by posterior reflection of the abductors, and reflection of short external rotators. It can be extended anteriorly into the first iliac window of the ilioinguinal incision.

The extended iliofemoral approach involves significant stripping of the bone, is associated with heterotopic bone formation, and an extended recovery period. Prolonged abductor weakness is to be expected. When necessary, this approach may be used to achieve reductions which are otherwise impossible.

Indications

• Transtectal associated transverse + posterior wall fractures, or T-shaped fractures, particularly with posterior wall comminution
• Transverse fractures with significant posterior wall involvement
• T-shaped fractures with widely displaced vertical limbs or pubic symphysis dislocation
• Both-column fractures with posterior wall or posterior column comminution, sacroiliac joint involvement, or very high posterior column involvement
• When ORIF of associated or transverse fractures is delayed by three or more weeks

The extended iliofemoral approach should not be used in aged or obese patients, nor in patients who are not committed to a long recovery process.

The following landmarks are used for orientation:

• Posterior superior iliac spine (PSIS)
• Iliac crest
• Anterior superior iliac spine (ASIS)
• Lateral margin of the knee

Incise the skin in the form of an inverted “J”. Begin at the PSIS and follow the iliac crest to the anterior superior iliac spine.

Reaching the ASIS, the incision is continued  along the anterolateral surface of the thigh for a length of 20-30 cm and halfway down the thigh. Proceeding distally, aim a bit posteriorly. This will allow easier posterior retraction of the musculocutaneous flap.

Expose the iliac crest from the ASIS towards the PSIS.

Develop the interval between the abdominal and the gluteal muscles. They have separate innervation and blood supply. The gluteal muscles will be mobilized, and the abdominal muscles left attached to the iliac crest.

Anteriorly, the interval between the sartorius and the tensor fasciae latae is developed from proximal to distal.

Deep dissection

• Exposure of the iliac wing
• Splitting of the fascia lata
• Release the insertion of gluteus minimus muscle
• Release the gluteus medius
• Release the external rotators
• Opening of the joint capsule

Wound Closure and Drains

• Start wound closure with the reattachment of the hip capsule.
• The external rotators are then reattached to the greater trochanter.
• Reattach the medius gluteus to the greater trochanter with strong sutures. Next repair the gluteus minimus tendon, recreating the original trochanteric insertion.
• Reattach the rectus femoris origin with transosseous sutures. If required, knee extension can be done to facilitate.
• Glutei, sartorius and abdominal muscles  are repaired followed by the fascia, subcutaneous tissue, and skin in layers.
• Drains are placed before closure, one along the posterior column, another in the distal portion of the incision, and a third in the internal iliac fossa, if it was exposed

Combined Approach

A simultaneous  combined  anterior  and posterior  approach  is possible with the  patient  in the ‘sloppy’ lateral position. The anterior approach is usually the iliofemoral, the posterior, or the Kocher- Langenbeck.