Long-term ankle brace use does not affect peroneus longus muscle latency during sudden inversion in normal subjects.

OBJECTIVE

External ankle supports are widely used in sports medicine. However, ankle bracing in a healthy ankle over a sustained period has been scrutinized due to possible neuromuscular adaptations resulting in diminished dynamic support offered by the peroneus longus muscle. Although this claim is anecdotal in nature, we sought to investigate the effects of long-term ankle bracing using 2 commonly available appliances on peroneus longus latency in normal subjects. Our second purpose was to evaluate the effects of ankle bracing on peroneus longus latency before a period of extended use.

DESIGN AND SETTING

A 3 x 3 x 2 design with repeated measures on the first and third factors was used in this study. All data were collected in the Sports Injury Research Laboratory.

SUBJECTS

Twenty (12 men and 8 women) physically active college students (age = 23.6 +/- 1.7 years; height = 168.7 +/- 8.4 cm; weight = 69.9 +/- 12.0 kg) free of ankle or lower extremity injury in the 12 months before the study and not involved in a strength-training or conditioning program in the 6 months before the study.

MEASUREMENTS

We evaluated peroneus longus latency by studying the electromyogram of the muscle after sudden foot inversion.

RESULTS

Application of a lace-up or semirigid brace did not affect peroneus longus latency. Additionally, 8 weeks of longterm ankle appliance use had no effect on peroneus longus latency.

CONCLUSIONS

The duration of the peroneus longus stretch reflex (latency) is neither facilitated nor inhibited with extended use of an external ankle support. Proprioceptive input provided by the muscle spindles within the peroneus longus does not appear to be compromised with the long-term use of ankle braces.