Below-knee cast speeds up recovery for severe ankle sprain

February 13, 2009,

(PhysOrg.com) -- Research led by the University of Warwick shows immobilising a severely sprained ankle in a below-knee cast for a short period of time promotes rapid recovery.

In an article published in this week’s edition of The Lancet, Professor Sallie Lamb from Warwick Medical School, and colleagues, concluded use of the below-knee cast or Aircast brace was more effective than other treatments that allowed a degree of mobility in the ankle.

Severe ankle sprains account for around 1.5 million UK emergency department attendances each year. These injuries are graded in severity from grade I (stretching of the ligament) to grade III (tear/complete rupture of the ligament complex). They are typified by inability to bear weight on the leg, and substantial swelling. Current treatment includes elevating the ankle and controlled mobilisation of the joint. Complete immobilisation is discouraged.

Professor Lamb and her colleagues assessed the effectiveness of three different mechanical supports (specialist boot, 10-day below-knee cast and the Aircast brace) compared with a double-layer tubular compression bandage in promoting recovery after severe ankle sprains. Including fitting, the specialist boot costs around £200, tubular compression bandage £1.44, the Aircast brace £39.23, and the below-knee cast £16.46 (2005 reference prices).

This randomised, controlled trial assessed 584 patients with severe ankle sprain from eight emergency departments across the UK. Patients were provided with a mechanical support within the first 3 days of attendance by a trained health-care professional, and given advice on reducing swelling and pain. Functional outcome was measured over 9 months. The primary outcome was quality of ankle function at 3 months.

The researchers found that patients who received the below-knee cast had a more rapid recovery than those given the tubular compression bandage. They noted clinically important benefits at 3 months in quality of ankle function with the below-knee cast compared with the bandage (mean difference 9%) as well as in pain, symptoms and activity.

The Aircast brace showed an 8% improvement in quality of ankle function at 3 months compared with the bandage; however these was little difference in pain, symptoms, and activity for those given the Aircast brace compared with the bandage. The specialist boot offered no advantage over the compression bandage. The differences between the treatments appear to be time sensitive, since at 9 months there was no significant difference between the bandage and the other treatments.

Professor Lamb said: "Contrary to popular clinical opinion, a period of immobilisation was the most effective strategy for promoting rapid recovery. This was achieved best by the application of a below-knee cast. The Aircast brace was a suitable alternative to below-knee casts.

“Results for the specialist boot were disappointing, especially in view of the substantial additional cost of this device. Tubular compression bandage, which is currently the most commonly used of all the supports investigated, was, consistently, the worst treatment.”

In an accompanying comment in The Lancet, Dr Jay Hertel, University of Virginia, Charlottesville, VA, USA, says: “Lamb and colleagues have presented provocative results that show the benefits of 10 days below-knee casting in patients with acute ankle sprains. Since short-term benefits were identified at 3 months, but intermediate-term benefits at 9-months follow-up were not found, the results of this study call into question the current standard of aggressive functional treatment of patients recovering from acute ankle sprains.”

Provided by University of Warwick

Related Stories

Recommended for you

Onions could hold key to fighting antibiotic resistance

January 22, 2018
A type of onion could help the fight against antibiotic resistance in cases of tuberculosis, a UCL and Birkbeck-led study suggests.

New long-acting approach for malaria therapy developed

January 22, 2018
A new study, published in Nature Communications, conducted by the University of Liverpool and the Johns Hopkins University School of Medicine highlights a new 'long acting' medicine for the prevention of malaria.

Virus shown to be likely cause of mystery polio-like illness

January 22, 2018
A major review by UNSW researchers has identified strong evidence that a virus called Enterovirus D68 is the cause of a mystery polio-like illness that has paralysed children in the US, Canada and Europe.

Creation of synthetic horsepox virus could lead to more effective smallpox vaccine

January 19, 2018
UAlberta researchers created a new synthetic virus that could lead to the development of a more effective vaccine against smallpox. The discovery demonstrates how techniques based on the use of synthetic DNA can be used to ...

Study ends debate over role of steroids in treating septic shock

January 19, 2018
The results from the largest ever study of septic shock could improve treatment for critically ill patients and save health systems worldwide hundreds of millions of dollars each year.

New approach could help curtail hospitalizations due to influenza infection

January 18, 2018
More than 700,000 Americans were hospitalized due to illnesses associated with the seasonal flu during the 2014-15 flu season, according to federal estimates. A radical new approach to vaccine development at UCLA may help ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.