title: The effects of multifocal refractive lenses on occipital extension and forward head posture during a visual task.
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.
authors.affiliation: College of Staten Island of The City University of New York, Department of Physical Therapy, 2800 Victory Boulevard, Staten Island, New York 10314, USA.
authors.forename: M
authors.initials: M
authors.lastname: Becker
authors.forename: J
authors.initials: J
authors.lastname: Rothman
authors.forename: A J
authors.initials: AJ
authors.lastname: Nelson
authors.forename: R
authors.initials: R
authors.lastname: Freedland
authors.forename: D
authors.initials: D
authors.lastname: Garcia
authors.forename: L
authors.initials: L
authors.lastname: Feit
authors.forename: J
authors.initials: J
authors.lastname: Barth
authors.forename: R
authors.initials: R
authors.lastname: Sabini
mesh_terms: D000328:Adult; D000368:Aged; D016288:Computer Terminals; D003261:Contact Lenses; D005260:Female; D005403:Fixation, Ocular / Q000502:physiology*; D006257:Head; D006801:Humans; D008297:Male; D008875:Middle Aged; D009519:New York City; D011187:Posture; D013647:Task Performance and Analysis; D014584:User-Computer Interface