Arthroscopic ankle fusion for avascular necrosis of the talus; a case series

A. Kendal, P. Cooke, R. Sharp

Background: Avascular necrosis (AVN) of the talus is a painful condition caused by trauma, steroids, alcoholism and haematological disorders. It is difficult to treat and at present there is insufficient evidence in favour of any particular strategy. The aim of operative therapy should be to relieve symptoms, maintain the normal architecture of the talus and treat associated arthritis. Small case series have described early core decompression, retrograde tibiotalocalcaneal arthrodesies and open tibio-calcaneal arthrodesis. Open procedures risk further talar collapse by disrupting its blood supply, and tibiotalocalcanal fusion sacrifices both the ankle and subtalar joints. The hypothesis is that arthroscopic ankle fusion relieves symptoms of AVN talus while preserving the subtalar joint and preventing further collapse.

Methods: A case study was performed of 16 patients with AVN who underwent arthroscopic ankle fusion at the Nuffield Orthopaedic Centre, Oxford, UK between 1998 and 2012. Clinical notes, radiographs and MRI was used to investigate the cause, co-morbidities and treatment outcomes following arthroscopic ankle fusion. Our primary outcome was fusion rate. Secondary outcomes included peri-operative complications, ongoing pain and subsequent operative intervention.

Results: The average age at the time of operation was 53.5 years (range 17 to 69). The presumed causes of AVN talus were steroids (3 patients), trauma (3 patients), haematological (2 patients), and alcoholism. The aetiology was unknown in 7 patients. Clinical and radiological fusion at the ankle joint was confirmed in 14/16 patients (2 were followed elsewhere). 11 patients were satisfied with the result at discharge, reporting no post operative complications. 3 patients had ongoing pain. 2 patients reported metalware irritation. 2 patients underwent a subsequent subtalar fusion.

Conclusions: Arthroscopic ankle fusion is a safe and reliable treatment of symptomatic AVN talus. It is a minimally invasive procedure potentially improving blood supply to the the talus and sparing the subtalar joint.