It is important to know a truer incidence of the need for subtalar and midfoot fusions, following an isolated ankle fusion, in order to better inform our patients of the likelihood of needing further surgery in the future. It is also important to understand whether pre-existing radiological arthrosis is likely to lead to the need for a fusion in the future and also how important the alignment of the ankle joint, after a fusion, may influence that.

The aim of the study is to review the patients' notes and radiology who have had a previous isolated ankle fusion and then to see whether they subsequently required further surgery.

Isolated ankle fusion is normally regarded as a good operation producing good pain relief and allowing patients to function well. Patients will have an early heel rise when walking and although that is often not immediately perceptible to an onlooker, it does increase the stress on the neighbouring subtalar and Chopart joints. Radiologically, subtalar joint arthrosis is common following isolated ankle fusions but not necessarily clinically symptomatic. The long term incidence of subsequent ipsilateral subtalar or Chopart joint fusions is not well known. Various different studies have shown a prevalence of osteoarthrosis (radiologically) of 24-100% in the subtalar joint and reported 84% of patients complaining of pain after 10 years. The prevalence in the Chopart joints has been reported to vary between 18-77%.

This is an observational study reviewing medical records and radiology of patients who have had an isolated ankle fusion. The data will be analysed using basic statistics with logistic regression modelling.

Inclusion Criteria:

Any patient who has had an isolated ankle fusion and is over the age of 18 years old.

Exclusion Criteria:

Participants younger than 18 years old.

Patients who have had an isolated ankle fusion.