Aetiology
- Most cases are post-traumatic after malleolar, pilon or talar fractures
- Chronic lateral ligament instability and varus malalignment
- Inflammatory arthritis, haemophilia and osteonecrosis of the talus
- Primary osteoarthritis is uncommon in the ankle
Assessment
- Pain, stiffness and deformity, with hindfoot alignment assessed standing
- Examine adjacent subtalar and midfoot joints, the soft tissue envelope and neurovascular status
- Weight bearing ankle and foot radiographs and a hindfoot alignment view
- CT or SPECT-CT shows adjacent joint disease and cysts
- Takakura classification grades varus ankle osteoarthritis from stage 1 to 4
Management
- Nonoperative care uses analgesia, activity change, a rocker sole, an ankle brace and injections
- Arthroscopic debridement helps anterior impingement
- Supramalleolar osteotomy suits asymmetric varus or valgus arthritis with preserved cartilage
- Arthrodesis is open or arthroscopic and is set in neutral dorsiflexion, 0 to 5 degrees of hindfoot valgus and 5 to 10 degrees of external rotation
- Total ankle replacement preserves motion in older, lower demand patients with good alignment and bone stock
- The TARVA trial found no significant difference in walking and standing scores at 52 weeks between replacement and fusion
Complications
- Fusion carries nonunion and later subtalar and midfoot arthritis
- Replacement carries wound problems, malleolar fracture, loosening and cysts, with revision or conversion to fusion
- Infection and nerve injury in both
Registry Data
Written by Western Health Orthopaedic Department
Last updated October 2026
Reviewed by Professor Phong Tran, Head of Orthopaedic Surgery, Western Health. Last updated 15 October 2026.