Measures of functional limitation as predictors of disablement in athleteswith acute ankle sprains

Study Design: Prospective multivariate design. Objectives: To determine the usefulness of activity scores, self-reported a thletic ability, and selected measures of physical impairment as predictors of disability duration in athletes with ankle inversion sprains. Background: Although several measures of physical impairment and functional limitation are used to assess the consequences of injury following ankle s prain, researchers have yet to establish which measures provide the most ac curate predictions of disability duration. Methods and Measures: Physical impairment, activity limitation, and disabil ity duration were measured in 21 athletes (13 men and 8 women; mean age = 2 0.3 +/- 1.7 years) with acute ankle sprains. Sagittal plane ankle range of motion and volumetric displacement were used as impairment indicators. Weig ht-bearing activity scores (task completion count) and self-reported athlet ic ability (visual analog scale) were used to represent functional limitati on. Elapsed time from injury to return to full athletic participation was u sed as the criterion measure of disability duration. Results: The impairment measures accounted for approximately one-third of t he variance in disability duration (R-2 = 0.342). Adding the activity limit ation measures to the regression model improved predictions of disability d uration (R-2 = 0.670; stepwise R-2 change = 0.328). The measures of activit y limitation alone, however, accounted for approximately 67% (R-2 = 0.665) Of the total variance in the number of days lost due to injury. Conclusion: Measures of activity limitation were the strongest predictors o f elapsed time from injury to return to full athletic participation.