Effect of Unifocal versus Multifocal Lenses on Cervical Spine Posture in Patients with Presbyopia


Significance: There are many environmental considerations which may or may not lead to the development of faulty cervical mechanics. The design of near vision lenses could contribute to the development of such cervical dysfunction and consequently neck pain. Decision making regarding proper type of lens prescription seems important for presbyopic individuals. Purpose: To investigate the effect of unifocal and multifocal lenses on cervical posture. Methods: Thirty subjects (18 females and 12 males) participated in the study with an age range from 40 to 64 years. Each subject wore consequently both unifocal and multifocal lenses randomly while reading. Then lateral cervical spine X-ray films were taken for each subject during each lens wearing. X-ray films were analyzed with digital software (Autocad software, 2 D) to measure segmental angles of the cervical vertebrae (Occiput/C1, C1/C2, C2/C3, C3/C4, C4/C5, C5/C6, C6/C7, C3/C7, C0/C3, and occiput/C7). Results: Higher significant extension angle in the segments C0/C7, C1/C2, C5/C6, C6/C7, and C3/C7 (p<0.05) during multifocal lenses wearing were observed in contrast with higher flexion angle between C3/C4 and C4/C5 (p<0.05) with unifocal lenses wear. Conclusion: Multifocal lens spectacles produces increased extension in the cervical vertebrae angles when compared with the use of unifocal lenses.


Rami Labib Abbas


Mouhamad Toufic Houri, Mohammad M Rayyan, Ibtissam Mouhamad Saab, Hamada Ahmed Hamada

Journal/Conference Information

International Journal of Occupational Safety and Ergonomics ,DOI:, ISSN: Print ISSN: 1080-3548, Volume: [Epub ahead of print], Issue: 4, Pages Range: 1-14