Imaging

All patients will have a preoperative standard ankle MRI scan after providing a written informed consent. Scans will be transferred via the Image Exchange Portal for assessment of presence or absence of OA in the adjacent talonavicular and subtalar joints, by a consultant radiologist at the Royal National Orthopaedic Hospital (RNOH), Stanmore, UK. Scans will be anonymised and stored at RNOH. The purpose of the MRI scan is to determine the presence or absence of adjacent-joint arthritis, as this is deemed by the investigating surgeons to be a confounding factor for prognosis and hence included as a stratifying variable in the randomisation.

No further MRI scans will be performed as part of the study. But a subsequent longer term imaging outcome study may be considered after 5–10 years subject to a further funding application.