Ankle Sprain

For rapid healing of a severely sprained ankle, think below-knee cast, according to investigators here. Action Points Explain to patients that this study showed that a below-knee cast leads to more rapid improvement in recovery from ankle sprain compared with other commonly used mechanical supports. Severe ankle sprains healed significantly more quickly with a below-knee cast or air-cell brace compared with a Bledsoe boot or a tubular compression bandage, investigators here reported. The 10-day below-knee cast and the Aircast resulted in 8% to 9% improvement in the quality of 90-day recovery compared with a tubular compression bandage, Sarah Lamb, D.Phil., of the University of Warwick, and colleagues reported in the Feb. 14 issue of The Lancet. The degree of improvement with the Bledsoe boot did not differ significantly from that of the tubular compression bandage, which was the least effective device. The quality of recovery at nine months did not differ among the four devices. "Contrary to popular clinical opinion, a period of immobilization was the most effective strategy for promoting rapid recovery," the authors said. "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 Bledsoe boot were disappointing, especially in view of the substantial additional cost of this device," they added. "Tubular compression bandage, which is currently the most commonly used of all the supports investigated, was, consistently, the worst treatment." Severe ankle injuries (grade II-III) can cause significant incapacitation and require three to nine months for recovery in most affected individuals, the authors noted. Systematic reviews have revealed lack of high-quality evidence to aid clinical decision-making related to management of severe ankle injuries. In an attempt to fill some of the data void, Dr. Lamb and colleagues performed a multicenter, randomized clinical trial involving 584 patients treated in eight emergency departments for severe ankle sprain. Participants were randomized to tubular compression bandage (reference), Bledsoe boot, 10-day below-knee cast, or Aircast. All patients began wearing the supports within three days of their injury. Trained healthcare professionals provided advice about use of the supports and strategies to reduce swelling and pain. The primary outcome was the quality of ankle function at three months, as determined by the standardized Foot and Ankle Score (FAOS). Evaluation of functional outcomes continued for nine months. After three months, patients assigned to tubular compression bandage had an average FAOS score of 54. Patients given the below-knee had a 9% improvement in recovery compared with the reference group (95% CI 2.4 to15, effect size 0.36). Support with the Aircast resulted in an 8% difference compared with the reference (95% 1.8 to14.2, ES 0.33) but there were little differences for pain, symptoms, and, activity. The Bledsoe boot led to a 6% improvement in FAOS versus the compression bandage, but the difference did not achieve statistical significance (95% CI 0 to12.3, ES 0.25). The below-knee cast and Aircast also led to greater improvement compared with the compression bandage on the FAOS subscales related to symptoms, pain, activities of daily living, and sports. although the Aircast brace was not as wide-ranging in its benefits as the below-knee cast, Patients assigned to the Bledsoe boot had mixed results on the subscales, including some scores that were worse than those of patients assigned to the compression bandage. The superior results in evidence at three months with the below-knee cast and Aircast were not sustained at nine months, as the four groups had similar levels of recovery. Scores on the physical and mental components of the SF-12 scale differed little among the four treatment groups. The results demonstrate advantages for the 10-day below-knee cast for patients with acute ankle sprains, Jay Hertel, Ph.D., of the University of Virginia in Charlottesville, said in a commentary. However, the results also failed to support widely used approaches to management of ankle sprains. "Since the short-term benefits were identified at three months, but the intermediate-term benefits at nine 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," said Dr. Hertel. The study was funded by the Department of Health in England. The authors and Dr. Hertel reported no potential conflicts of interest.

Primary source: The Lancet Source reference: Lamb SE, et al "Mechanical supports for acute, severe ankle sprain: A pragmatic, multicentre, randomized controlled trial" Lancet 2009; 373: 575-581. Additional source: The Lancet Source reference: Hertel J "Immobilization for acute severe ankle sprain" Lancet 2009; 373: 524-526.