Anterolateral Approach to Lateral Plateau

The anterolateral approach to lateral plateau of tibia is used mainly for open reduction and internal fixation of fractures of the lateral tibial plateau.

Other uses of the anterolateral approach to lateral plateau of tibia include:

1. Bone grafting for delayed union and nonunion of fractures.
2. Treatment of osteomyelitis.
3. Excision and biopsy of tumors.
4. Proximal tibial osteotomy.
5. Harvesting of bone graft.

The anterolateral approach is preferred to a direct anterior approach to the tibia because the skin in the anterolateral approach does not directly overlay the bone.

Position of the Patient

• Place the patient supine on a radiolucent table.
• Place a firm wedge beneath the knee to flex the joint to approximately 60º .
• Place a small bag underneath the buttock to correct the normal external rotation of the lower limb, this will ensure that the patella is facing directly anteriorly.

See Also: High tibial osteotomy

Landmarks and Incision

• Landmarks:
  • The shaft of the proximal tibia along its anterior border.
  • Lalateral joint line.
  • Gerdy’s tubercle.
• Incisin:
  • Make an S-shaped incision. Start approximately 3 to 5 cm proximal to the joint line, staying just lateral to the border of the patella tendon.
  • Curve the incision anteriorly over Gerdy’s tubercle and then extend it distally, staying about 1 cm lateral to the anterior border of the tibia.
  • The exact length of the incision depends on the pathology to be treated and the implant to be used.

Internervous plane

• There is no internervous plane in the anterolateral approach to lateral plateau.
• The dissection is essentially epi-periosteal and does not disturb the nerve supply to the extensor compartment.

Superficial dissection

• Deepen the incision proximally through subcutaneous tissue to expose the lateral aspect of the knee joint capsule.
• Incise the knee joint capsule longitudinally down to the superior border of the lateral meniscus.
• Below the joint line, deepen the incision through subcutaneous tissue and incise the fascia overlying the tibialis anterior muscle.

Deep dissection

• Proximally enter the knee joint by dividing the synovium.
• Carefully detach the lateral meniscus from its soft-tissue attachments inferiorly and develop a plane between the undersurface of the lateral meniscus and the underlying tibial plateau.
• Insert stay sutures to the periphery of the meniscus to facilitate reattachment during closure.
• Detach a sufficient amount of the meniscus to allow adequate visualization of the superior surface of the lateral tibial plateau.
• Using an elevator, inferiorly detach some of the origin of tibialis anterior from the proximal tibia.
• Try to work in a plane between the periosteum and the muscle.

Approach Extension

Proximal Extension:

• To extend the anterolateral approach to lateral plateau proximally, continue the skin incision along the lateral aspect of the patella, then curve posteriorly over the lateral aspect of the distal femur.
• Deepen the incision through the lateral joint capsule to gain access to the knee joint and the distal femur proximally.

Distal Extension:

• To extend the approach distally, continue the incision in a longitudinal fashion, remaining 1 cm lateral to the anterior border of the tibia.
• Extend it all the way down to the ankle proximally.
• Deep dissection, either by splitting the tibialis anterior muscle or by detaching it from the lateral aspect of the tibia, allows access to the tibial shaft down to its proximal quarter.

Dangers

The structures at risk during the anterolateral approach to lateral plateau include:

1. The superficial branch of the peroneal nerve: it lies well posterior to the area of dissection and it should not be injured.
2. The lateral meniscus: Take care not to completely detach it, preserving anterior and posterior attachments, however.

References

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