Osteochondral lesions (OCL) of the talus occur in 38% of the patients with supination external rotation type IV ankle fractures and 6 % of ankle sprains. Osteoarthritis is reported subsequently in 8–48% of the ankles. Several marrow stimulation methods have been used to treat the symptomatic lesion, including arthroscopic debridement and micro fracture. Encouraging midterm results have been reported, but longterm outcome is unknown in relation to more invasive treatments such as transfer of autologous osteoarticular tissue from the knee or talus (OATS), autologous chondrocyte implantation (ACI), frozen and fresh allograft transplantation.

Hind and mid foot arthritis is often noted in patients who have previously had an ankle arthrodesis. It has been suggested that this arthritis may be precipitated or exacerbated as a direct result of the ankle fusion. The aim of this study was to investigate the degree and pattern of pre-existing ipsilateral foot arthritis in patients who have subsequently undergone ankle arthrodesis.

A retrospective review of the most recent pre-operative radiographs of 70 patients who underwent 71 arthrodeses between 1993-2003 was performed. Patients with rheumatoid disease were excluded. The immediate pre-operative AP and lateral ankle radiographs were assessed and the presence and severity of osteoarthritis for the sub-talar, talo-navicular, naviculo-cuneiform and calcaneo-cuboid joints was recorded using the Kellgren and Lawrence grading score. This was performed simultaneously by two reviewers and a consensus obtained. A total score out of 16 was given for each radiograph.

68 (96%) of the radiographs reviewed showed evidence of pre-existing hind or mid foot arthritis prior to ankle fusion. The sub-talar joint was the most commonly and severely affected. The median total arthritis score for each radiograph was 5. There was no association between age or causative pathology and the degree of arthritis.

This study has demonstrated that hind and mid foot arthritis is very common in patients with co-existent ankle arthritis prior to ankle fusion. This has previously been assumed to have developed as a result of the surgery but is, in fact, present at the time of the operation and this needs to be taken into consideration when evaluating the results of ankle arthrodesis

Introduction

Scaphoid fracture is the most common undiagnosed fracture. Occult scaphoid fractures occur in 20-25 percent of cases where the initial X-rays are negative. Currently, there is no consensus as to the most appropriate investigation to diagnose these occult frctures. At our institution MRI has been used for this purpose for over 3 years. We report on our experience and discuss the results.