New research published by the National Institute for Health Research Health Technology Assessment (NIHR HTA) programme has found that the most clinically and cost-effective treatment for pain relief and recovery from severe ankle sprain, where patients cannot put any weight through that leg, is a below the knee plaster cast.

There are a number of different treatments for severe ankle injuries including no intervention, physiotherapy, different types of supports, immobilisation, and surgical repair of the ligaments. However, there is a lack of good quality evidence to help aid clinical decision-making as to which is the best treatment.

The clinical trial, led by Professor Matthew W Cooke of the Warwick Medical School & Heart of England NHS Foundation Trust and Professor Sallie Lamb of Warwick Medical School assessed the clinical and cost-effectiveness of four methods of ankle support. A below the knee plaster cast; an aircast plastic splint; and a 'ski boot' style support were compared to a double layer tubular compression bandage, chosen as the reference treatment. The ankle supports were assessed in terms of recovery of function, recovery of normal occupation and prevention of residual problems. Eight emergency departments across the UK participated in the trial and researchers recruited around 600 patients with the most severe ankle sprains. They were randomised to receive one of the four treatments. Patients could still have other treatments as usual, such as painkillers and medical creams to ease pain. They were followed up with questionnaires over a nine month period to assess mobility following treatment.

Researchers found that the below knee plaster case was best at relieving pain at four and 12 weeks. The aircast plastic splint and the ski boot offered no significant advantage over the compression bandage. After 9 months there was little difference between patients regardless of the intervention they received. While the compression bandage was the cheapest option (£1.44), the plaster cast was so much better at relieving pain that it was the most cost-effective intervention.

"Our aim was to measure which treatment was the most beneficial ankle support for patients, enabling them to continue their daily routine with minimum discomfort and to aid a faster healing process, as well as being cost-effective." says Professor Cooke. "All treatments are available through the NHS and the findings of the trial will help inform clinicians' decisions on the most effective method to use for severe ankle sprains."

Professor Cooke went on to advise, "there were no differences in the patients wellbeing in the long term following all four treatments, so it would be beneficial to select an ankle support that is preferred by the patient as this could affect the speed of recovery."

To view and download the full report visit The results of the trial also published in The Lancet Volume 373, Issue 9663, pages 575 - 581, 14 February 2009.

1. The Ski Boot support used was the Bledsoe Boot which supports the ankle and has a hinge to allow for movement.

2. The HTA programme is a programme of the National Institute for Health Research (NIHR) and produces high quality research information about the effectiveness, costs, and broader impact of health technologies for those who use, manage and provide care in the NHS. It is the largest of the NIHR programmes and publishes the results of its research in the Health Technology Assessment journal, with over 400 issues published to date. The journal's 2007 Impact Factor (3.87) ranked it in the top 10% of medical and health-related journals. All issues are available for download free of charge from the website, The HTA programme is coordinated by the NIHR Coordinating Centre for Health Technology Assessment (NCCHTA), based at the University of Southampton.

3. The National Institute for Health Research provides the framework through which the research staff and research infrastructure of the NHS in England is positioned, maintained and managed as a national research facility. The NIHR provides the NHS with the support and infrastructure it needs to conduct first-class research funded by the Government and its partners alongside high-quality patient care, education and training. Its aim is to support outstanding individuals (both leaders and collaborators), working in world class facilities (both NHS and university), conducting leading edge research focused on the needs of patients.

National Institute for Health Research