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Date of Award


Degree Type

Thesis (On-Campus Access Only)

Degree Name

Master of Physical Therapy (MPT)

First Advisor

Ann Williams, PhD, PT

Second Advisor

Jay Salzman, BS, PT


Many quantitative methods for assessing standing balance have been developed. One of the most common methods of measuring balance is postural sway. Static and dynamic postural sway utilizing force platforms or other instruments have been used with the test position primarily in bilateral stance. Limited data is available with regards to postural sway on a force plate system during one-legged stance among healthy, young adults. Therefore, the purpose of this study was to establish baseline values of postural sway and to determine the mean center of pressure in the sagittal and lateral planes during one-legged stance with eyes opened and closed. Thirty-three active, healthy, young adults between the ages of 18 to 37 years were tested in the one-legged stance position for 10 seconds using the eyes opened and eyes closed test conditions for each leg. The mean postural sway amplitude values during one-legged stance were 11.98 (SD = 2.93) for the eyes opened test condition and 27.67 (SD= 6.33) for the eyes closed test condition. A significant difference for postural sway amplitude between the eyes opened and eyes closed test conditions was found [F(1,60) = 13.30, P = 0.0001]. No significance was found between the genders for postural sway amplitude in the two conditions for either leg. For the dominant leg, eyes closed condition, the center of pressure for females was significantly more towards their toes (p=0.01). While 100% of the subjects were able to complete the eyes opened test on the first trial, only 54.8% (dominant leg) and 51.7% (non-dominant leg) were able to complete their first trial with the eyes closed test.


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