Peroneus longus muscle activation pattern during gait cycle in athletes affected by functional ankle instability: a surface electromyographic study.
BACKGROUND
Functional ankle instability is a clinical syndrome that may develop after acute lateral ankle sprain. Although several causes of this functional instability have been suggested, it is still unclear what the activation pattern of the peroneus longus muscle is in patients with functional ankle instability.


OBJECTIVE
Peroneus longus activation patterns differ in the injured side and the uninjured side in subjects with functional ankle instability.


METHODS
Descriptive laboratory study.


METHODS
The authors examined 14 subjects with functional ankle instability by using surface electromyography during walking. Activation time of the peroneus longus muscle was expressed as a percentage of the stance phase of the gait cycle.


RESULTS
A statistically significant decrease in peroneus longus muscle activity was found in the injured side compared with the uninjured side (22.8% +/- 4.25% vs 37.6% +/- 3.5%, respectively).


CONCLUSIONS
Results obtained in this study show a change in peroneus longus muscle activation time after injury. Independent of the origin of this change, which could only be surmised, the decrease in peroneus longus muscle activity may result in reduced protection against lateral sprains.


CONCLUSIONS
The assessment of peroneus longus activation pattern during gait is useful to design an appropriate rehabilitation program in athletes suffering from functional ankle instability.
Board of Physical Medicine and Rehabilitation, University La Sapienza, Rome, Italy.
Valter
V
Santilli
Massimo A
MA
Frascarelli
Marco
M
Paoloni
Flaminia
F
Frascarelli
Filippo
F
Camerota
Luisa
L
De Natale
Fabio
F
De Santis
D000293:Adolescent; D000328:Adult; D000843:Ankle Joint; D004576:Electromyography; D005260:Female; D005684:Gait; D006801:Humans; D007593:Joint Instability / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D018482:Muscle, Skeletal / Q000294:innervation / Q000503:physiopathology*; D013180:Sprains and Strains / Q000150:complications; D016138:Walking / Q000502:physiology