- Iliofemoral approach
The iliofemoral approach and the approach named after Smith-Peterson share a similar skin incision but differ markedly in the deep exposure provided.
This approach provides access to the iliac crest and the entire internal iliac fossa.
The fossa exposure incorporates full visualization of the anterior aspect of the sacroiliac joint, if needed.
The medial limit of the exposure is expanded medially to the iliopectineal eminence when the ipsilateral limb is prepped free and the hip can be flexed to 60-90 degrees and adducted.
This approach also provides digital and limited visual access to the quadrilateral surface and greater sciatic notch.
Our image shows
- in dark brown: Direct access
- in light brown: Limited visual and digital or clamp access
Some fractures of the anterior column can be operated through the iliofemoral approach. This is also true for associated anterior + posterior hemitransverse fractures.
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.
Occasionally, this approach can also be utilized to address the anterior column component of a T-type fracture. In this setting, the posterior column is addressed through a second sequential Kocher-Langenbeck approach.
The proximal end of the skin incision parallels the iliac crest and begins posterior to the gluteus medius pillar.
The actual position of the skin incision relative to the crest may need to be modified depending on the body habitus of the patient.
Scars directly over the iliac crest in thin patients are poorly tolerated.
In heavier patients incisions through the intertriginous zones should be avoided. This usually requires making the incision somewhat proximal or distal to the crest in these individuals.
Extension of the incision
Classically, this incision would be then extended all the way to the anterior superior iliac spine, and then continued distally along the interval between the sartorius and tensor muscle.
A prudent modification of the superficial dissection stops the anterior extent of the proximal limb of the skin incision 1-2 cm lateral to the anterior superior iliac spine.
It then extends distally and laterally directly over the anterior aspect of the tensor muscle belly.
This limits to some extent the skin problems encountered at the junction of the two limbs of the incision. It also minimizes the cutaneous sensory loss by reducing the number of branches of the lateral cutaneous nerve of the thigh which have to be sacrificed for the exposure.
Superficial surgical dissection
The exposure is deepened through the subcutaneous layer and the external oblique muscle is released from the crest taking care to leave a thick fascial/periosteal cuff to facilitate subsequent repair.
This release starts posteriorly where the oblique overhangs the crest and extends anteriorly to the level of an anterior superior iliac spine osteotomy or sartorius/inguinal ligament release (see next step).
In continuity with the release of the external oblique a subperiosteal exposure of the internal iliac fossa is begun by lifting the iliacus muscle.This interval is then packed with a sponge until the distal exposure is further developed.
Osteotomy of ASIS
In some cases it is possible to facilitate the deep exposure by osteotomizing the anterior superior iliac spine.
The bone block released with this technique typically measures 1 cm in depth and 2 cm in anterior-posterior length.
The tensor attachment in this area is released to facilitate the osteotomy, and the bone block is displaced medially with the external oblique and iliacus. Also attached to the bone block are the sartorius origin and inguinal ligament.
This technique should be avoided in fracture patterns which encroach on the area of the osteotomy.
Variation: Sharp release of sartorius and inguinal ligament
When the fracture pattern does not permit 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 as a single cuff of tissue.
Starting 1-2 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 tensor-sartorius interval may be palpable in some patients as a guide.
The incision is extended distally at least 12-15 cm for the typical exposure.
The tensor muscle is retracted laterally and the medial sheath of the tensor fascia is retracted medially protecting the major trunk(s) of the lateral femoral cutaneous nerve.
Secure the lateral circumflex vessels
The further deep dissection proceeds through the “floor” of the tensor sheath.
Distally, approximately 10 cm from the ASIS 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.
Provide access to the true pelvis
At this point the proximal and distal limbs of the exposure are effectively joined.
Further visualization is best achieved with hip flexion and adduction to reduce the tension on the iliopsoas.
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.
Medial retraction in the distal portion of the exposure must be undertaken carefully, particularly in the extended hip.
Sustained retraction or pronounced medial displacement of the iliopsoas places the femoral nerve at some risk of neuropraxic injury.
Perform the arthrotomy
In some cases it my be useful to perform an 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 with Homan retractors.
It may be necessary to release the reflected head of the rectus.
A T-shaped arthrotomy is then carried out, taking care not to injure the underlying acetabular labrum.
The closure begins with loose repair of the capsule when needed.
Deep drains are placed.
The external oblique is repaired to the iliac crest. This can be done through drill holes or with simple fascial/periosteal repair if tissue integrity is adequate.
When present, the ASIS 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 and this is followed by appropriate subcutaneous and skin closure.