Therapeutic ultrasound for acute ankle sprains

 

Abstract

Background

Ultrasound is used in the treatment of a wide variety of musculoskeletal disorders.

Objectives

To evaluate the effects of ultrasound therapy in the treatment of acute ankle sprains.

Search strategy

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (July 2004), the Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 2, 2004), MEDLINE (1966 to July 2004), EMBASE (1983 to July 2004), CINAHL (1982 to July 2004), and PEDro - the Physiotherapy Evidence Database (http://ptwww.cchs.usyd.edu.au/pedro/) (accessed 17/09/04). We also searched the Cochrane Rehabilitation and Related Therapies Field database, reference lists of articles, and contacted colleagues.

Selection criteria

Randomised trials were included if the following conditions were met: at least one study group was treated with active ultrasound; participants had acute lateral ankle sprains; and outcome measures included general improvement, pain, swelling, functional disability, or range of motion. Final selection of papers was conducted by two authors independently.

Data collection and analysis

Two authors independently assessed quality using a standardised checklist and extracted data. Relative risks together with 95 per cent confidence intervals were calculated for dichotomous outcomes and weighted or, where different scales were used, standardised mean differences together with 95 per cent confidence intervals for continuous outcome measures. Pooling of data was undertaken where there was clinical homogeneity in terms of participants, treatments, outcomes, and follow-up time points.

Main results

Five trials were included, involving 572 participants. Four of these trials were of modest methodological quality and one placebo-controlled trial was considered to be of good quality. None of the four placebo-controlled trials (sham ultrasound) demonstrated statistically significant differences between true and sham ultrasound therapy for any outcome measure at seven to 14 days of follow up. The pooled relative risk for general improvement was 1.04 (random-effects model, 95% confidence interval 0.92 to 1.17) for active versus sham ultrasound. The differences between intervention groups were generally small, between zero and six per cent for most dichotomous outcomes. However, one trial reported relatively large differences for pain-free status (20%) and swelling (25%) in favour of ultrasound.

Authors' conclusions

The extent and quality of the available evidence for the effects of ultrasound therapy for acute ankle sprains is limited. The results of four placebo-controlled trials do not support the use of ultrasound in the treatment of ankle sprains. The magnitude of treatment effects are generally small and of limited clinical importance. As yet, only few trials are available and no conclusions can be made regarding any optimal dosage schedule for ultrasound therapy, and whether such a schedule would improve the reported lack of effectiveness of ultrasound for ankle sprains.

 

Plain language summary

Therapeutic ultrasound for acute ankle sprains

Ultrasound, or the use of high frequency sound pulses, is commonly used for treating acute ankle sprains. It is thought that the increase in temperature caused by ultrasound helps soft tissue healing. This review of trials found that ultrasound therapy does not seem to help to reduce pain and swelling, or to improve the ability to stand on the affected foot. Most injuries heal quickly within about two weeks, and ultrasound does not seem to hasten recovery. Most trial results do not support the use of ultrasound, as any differences in effect are very small.