Hip and knee muscle torque is not impaired in the first three months of a first-time lateral ankle sprain.

OBJECTIVES

The primary objective was to compare hip and knee isometric muscle strength between individuals with a first-time acute lateral ankle sprain and controls. A secondary objective was to investigate hip and knee isometric muscle strength three months post-injury.

DESIGN

Cross-sectional and prospective follow-up components.

SETTING

Laboratory environment.

PARTICIPANTS

Forty-two participants (21 acute lateral ankle sprain and 21 controls) matched for age, sex, physical activity and leg dominance participated.

MAIN OUTCOME MEASURES: Hip and knee isometric muscle torque was assessed using a rigidly fixated hand-held dynamometer. Testing in acute lateral ankle sprain participants was performed within four weeks of injury and three months post-injury. Controls were tested at one timepoint.

RESULTS

There were no differences in hip or knee isometric muscle torque between acute lateral ankle sprain and control participants (mean differences <0.08). Hip and knee isometric muscle torque in acute ankle sprain participants did not differ between baseline and three months post-injury testing (mean difference <0.06).

CONCLUSIONS

Proximal lower limb isometric strength is not impaired within the first three months of sustaining a first-time lateral ankle sprain injury. This implies that hip and knee isometric strength deficits in individuals with CAI may occur at some later stage.