Unipedal stance testing as an indicator of fall risk among older outpatients

Objective: To test the hypothesis that a decreased unipedal stance time (UST) is associated with a history of falling among older persons. Design: Fifty-three subjects underwent a standardized history and physical examination and three trials of timed unipedal stance. Setting: The electroneuromyography laboratories of tertiary care Veterans Administration and university hospitals. Subjects: Ambulatory outpatients 50 years and older referred for electrodiagnostic studies. Outcome Measures: UST and fall histories during the previous year. Results: Twenty subjects (38%) reported falling. Compared with the subjects who had not fallen, those who fell had a significantly shorter UST (9.6 [SD 11.6] vs 31.3 [SD 16.3] seconds, using the longest of the three trials, p <.00001). An abnormal UST (<30sec) was associated with an increased risk of having fallen on univariate analysis and in a regression model (odds ratio 108; 95% confidence interval 3.8, >100; p <.007). The sensitivity of an abnormal UST in the regression model was 91% and the specificity 75%. When UST was considered age was not a predictor of a history of falls. Conclusions: UST of <30sec in an older ambulatory outpatient population is associated with a history of falling, while a UST of greater than or equal to 30sec is associated with a low risk of falling.