Approach to the Lateral Malleolus indications:

The approach to the lateral malleolus is used primarily for open reduction and internal fixation of lateral malleolar fractures.

The approach to the lateral malleolus other uses include:

  1. Open reduction and internal fixation of syndesmosis ligaments.
  2. Percutaneous placement of syndesmosis screws.
  3. Access to the posterolateral tibia.

Position of the Patient

  • Place the patient supine on the operating table with a sandbag under the buttock of the affected limb. The sandbag causes the limb to rotate medially, bringing the lateral malleolus forward and making it easier to reach
Approach to the Lateral Malleolus

Landmarks and Incision

  • Landmarks:
    • Lateral malleolus.
    • The short saphenous vein
  • Incision:
    • Make a 10- to 15-cm longitudinal incision along the posterior margin of the fibula all the way to its distal end and continuing for a further 2 cm. In fracture surgery, center the incision at the level of the fracture.
Approach to the Lateral Malleolus

Internervous plane

  • There is no internervous plane for the approach to the lateral malleolus because the dissection is being performed down to a subcutaneous bone.
  • For higher fractures of the fibula, the internervous plane lies between the peroneus tertius muscle which is supplied by the deep peroneal nerve and the peroneus brevis muscle which is supplied by the superficial peroneal nerve.

Superficial dissection

  • Elevate the skin flaps, taking care not to damage the short saphenous vein, which lies posterior to the lateral malleolus. The sural nerve, which runs with the short saphenous vein, also should be preserved.

Deep dissection

  • Incise the periosteum of the subcutaneous surface of the fibula longitudinally, and strip off just enough of it at the fracture site to expose the fracture adequately. Take care to keep all dissection strictly subperiosteal, because the terminal branches of the peroneal artery, which lie close to the lateral malleolus, may be damaged.
  • Only strip off as much periosteum as is necessary for accurate reduction; periosteal stripping markedly reduces the blood supply of the bone in cases of fracture.

Approach Extension

Proximal Extension:

  • Extend the incision along the posterior border of the fibula, incising the deep fascia in line with the skin incision.
  • Develop a new plane between the peroneal muscles which are supplied by the superficial peroneal nerve and the flexor muscles which are supplied by the tibial nerve.
  • The upper third of the fibula can be exposed if the common peroneal nerve can be identified near the knee and traced down toward the ankle.
See Also: Lateral approach to the fibula.

Distal Extension:

  • To extend the approach distally, curve the incision down the lateral side of the foot.
  • Identify the peroneal tendons and incise the peroneal retinacula.
  • Detach the fat pad in the sinus tarsi and the origin of the extensor digitorum brevis muscle to expose the calcaneocuboid joint on the lateral side of the tarsus

The approach to the lateral malleolus may be extended distally to become continuous with:

  1. Ollier’s lateral approach to the tarsus.
  2. Kocher lateral approach to the ankle and tarsus.
  3. Lateral approach to the calcaneus.

Posterior Extension:

  • Can access posterolateral tibia for fixation.
  • Interval is between the peroneal muscles/tendons and flexor hallucis longus.

Dangers

The structures at risk during the approach to the lateral malleolus include:

  1. Sural nerve:
    • It’s injury may lead to formation of a painful neuroma and numbness along the lateral skin of the foot.
  2. Short Saphenous vein.
  3. Terminal branches of peroneal artery:
    • They lie deep to medial surface of distal fibula.
    • They can be damaged if dissection does not stay subperiosteal, and may form hematoma after removal or tourniquet.
  4. Superficial peroneal nerve:
    • The Superficial peroneal nerve crosses from posterior to anterior over the fibular shaft at the proximal end of the incision.

References

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