@article{ref1,
title="The effects of multifocal refractive lenses on occipital extension and forward head posture during a visual task",
journal="Ergonomics",
year="2007",
author="Becker, M. and Rothman, J. and Nelson, A. J. and Freedland, R. and Garcia, D. and Feit, L. and Barth, J. and Sabini, R.",
volume="50",
number="12",
pages="2095-2103",
abstract="The purpose of this study was to determine if a change in forward head posture and occipital extension occurred in participants who wore multifocal lenses vs. those persons with non-multifocal lenses while performing an 8-min visual reading task on a visual display unit (VDU). Forty-two healthy human participants were recruited for this study. Thirty-three participants completed the study. Fourteen participants wore multifocal lenses and 19 wore frames with non-multifocal lenses. To evaluate the degree of change of forward head posture and occipital extension digital photographs of cervical posture were taken at four different time intervals: prior to performing the reading task and at 3, 5 and 8 min during the reading task. The digital photographs were analysed utilizing a computer program. Two one-way ANOVA were utilized to determine the degree of change of forward head posture and occipital extension between groups. A significant difference was identified between groups for changes in degrees of forward head posture while performing a visual reading task on a VDU. However, no significant difference between groups was found for occipital extension while performing the same task. Multifocal wearers exhibit greater degrees of change in forward head posture and occipital extension than non-multifocal wearers. These postural changes may place them at a greater risk for musculoskeletal disorders and headaches.<p /><p>Language: en</p>",
language="en",
issn="0014-0139",
doi="10.1080/00140130701419166",
url="http://dx.doi.org/10.1080/00140130701419166"
}