The effect of immersion cryotherapy on medial-lateral postural sway variability in individuals with a lateral ankle sprain.

BACKGROUND AND PURPOSE: Postural stability has been shown to be impaired after a lateral ankle sprain (LAS) and after immersion cryotherapy in healthy ankles. This study was performed to determine the effects of cryotherapy on postural stability after LAS.

METHOD: A single-session, repeated measures design was used. Fifteen 18- to 29-year-old males (mean age 21.33 +/- 3.54, height 71.23 +/- 2.50 cm, mass 170.33 +/- 19.77 kg) with relatively recent grade I LAS volunteered. Medial-lateral postural sway variability was assessed during single-leg barefoot stance using a Bertec force platform. Sway was tested before cryotherapy ('Pre'), immediately after 20 minutes of lower-leg immersion cryotherapy ('Post(0)'), and 10 and 20 minutes after cryotherapy ('Post(10)' and 'Post(20)'). Both legs were tested (individually) before cryotherapy; the involved leg was tested alone after cryotherapy. The uninvolved leg served as a control.

RESULTS

Postural sway variability of the involved le was significantly greater than the uninvolved le before cryotherapy (p = 0.001). Postural sway variability of the involved leg was also significantly greater than the uninvolved LE during Post(0) (p = 0.000), Post(10) (p = 0.000) and Post(20) testing (p = 0.003) with the largest increase in sway variability occurring at Post(0).

CONCLUSIONS

Medial-lateral postural sway variability was greater after LAS. This effect was augmented by immersion cryotherapy.