Posterolateral approach to the Ankle

Indications

arthrodesis of posterior facet of subtalar joint

Position

prone
longitudinal bolsters for chest & abdomen

Landmarks

lateral malleolus
achilles tendon

Incision

10 cm straight longitudinal incision between posterior border of lateral malleolus & lateral border of Achilles tendon

Internervous Plane

Peroneus brevis
- Superficial peroneal nerve
Flexor hallucis longus
- Tibial nerve

Superficial Dissection

Mobilise skin flaps
- Taking care not to damages
  - Short saphenous vein
  - Sural nerve
  - These however should be well anterior of incision
Incise deep fascia of leg
Identify peroneus longus & brevis
- Brevis is closer to lateral malleolus & is muscular almost down to ankle
Incise the peroneal retinaculum to release the tendons
Retract muscles anteriorly to expose FHL
- Most lateral of deep flexor muscles
- Only one muscular at this level

Deep Dissection

If needed
- Reflect FHL fibres from fibula
- Retract FHL medially to expose ankle joint

Dangers

Nerves
- Short saphenous vein
Vessels
- Sural nerve