Clinical trial NCT02656953: The Impact of Lenses on Musculoskeletal and Visual Complaints in VDU Workers With Neck Complaints
Official title: The Impact of Wearing VDU Lenses Versus Progressive Lenses on Musculoskeletal and Visual Complaints in VDU Workers With Work Related Neck Complaints: A Randomized Controlled Trial
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Neck Pain
Keywords: VDU workers
VDU lenses
Neck complaints
Visual complaints
Lead sponsor: University Ghent
Sponsor class: OTHER
First posted: 2016-01-15
Enrollment: 40
Sex: ALL
Minimum age (years): 45
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: OTHER

Brief summary: The aim of this study is to investigate the impact of wearing visual display units (VDU) lenses versus progressive lenses on musculoskeletal and visual complaints in VDU workers with work related neck complaints. This will be evaluated by means of questionnaires (Neck Disability Index and Visual Fatigue Questionnaire), muscle tone, elasticity and stiffness, pressure pain threshold and 2D video analysis of head posture during a VDU task.

Detailed description: The use of visual display units (VDU) is often accompanied by physical complaints of the neck, shoulder, forearm and hand, especially in people who make extensive use of computers at work. Besides this, VDU operators also experience eye discomfort and vision problems when working with the computer for a long period.

With the increase of computer use, VDU glasses were developed. They provide a clear vision of the intermediate zone at a distance of approximately 70 centimeters, which is closer than distant vision at a distance of more than 2 meters (e.g. driving), but further than near vision at a distance of 40 centimeters (e.g. reading), so the computer screen is seen clear without the need for excessive focusing effort or bad postures. Progressive lenses have some lens power for this intermediate zone as well, but this zone might not be large enough for comfortable and ergonomic computer work. VDU glasses are often progressive glasses as well, so they can be used to read and see things beyond the computer screen clear during computer work.

The research question of this study is "What is the impact of wearing progressive VDU lenses versus progressive lenses, for six months, on both musculoskeletal and visual complaints in VDU workers with work related neck complaints ?"

To find an answer to this question, 40 VDU workers (men and women) with work related neck/shoulder complaints, were recruited from a bank office where they perform predominantly VDU work. All participants will receive information and have to sign an informed consent form.

A questionnaire concerning visual and musculoskeletal complaints, in which the Neck Disability Index (NDI) Questionnaire had to be completed at the beginning of the experiment. Participants were tested with their old glasses in a landscape office while performing a 20 minute VDU task. Before and after the task, viscoelastic properties (MyotonPRO®) of the trapezius muscle and the PPT (WagnerTM FDX 50 hand-held pressure algometer) of the trapezius muscle, the levator scapulae muscle and the infraspinatus muscle were measured. A 2D video analysis was performed during the task.The Forward Head Angle (FHA) and the Forward Shoulder Angle (FSA) was measured afterwards. After this, participants were asked to fill out a short questionnaire, in which the Visual Fatigue Questionnaire was included, every two weeks during two months. On the 15th of June, 2015 the participants received new glasses and were asked to wear these for six months during computer work. During this period the same short questionnaire had to be filled out every two weeks. The test procedure will be repeated with the new glasses after six months of wearing these. A shorter version of the first questionnaire will be completed at the end of the experiment.

Eligibility criteria: Inclusion Criteria:

* Minimum 4 hours a day and 20 hours a week of VDU work
* Work related neck/shoulder complaints
* Difference in spectacle correction for presbyopia and myopia of minimum 1.5 dioptres

Exclusion Criteria:

* Active eye disease that can't be corrected with eyeglasses
* Drugs that strongly influence eye or muscle function

Primary outcomes:
measure: Change in functionality using the Neck disability index (NDI)
timeFrame: At baseline and six months
measure: Change in visual complaints using the Visual Fatigue Questionnaire
timeFrame: At baseline and six months
Secondary outcomes:
measure: Change in muscle elasticity by using the MyotonPRO® device
timeFrame: At baseline and six months
measure: Change in muscle stiffness by using the MyotonPRO® device
timeFrame: At baseline and six months
measure: Change in muscle tone by using the MyotonPRO® device
timeFrame: At baseline and six months
measure: Change in pressure pain threshold by using the WagnerTM FDX 50 hand-held pressure algometer
timeFrame: At baseline and six months
measure: Change in head posture during a VDU task by means of 2D video analysis
timeFrame: At baseline and six months
Other outcomes:
Locations:
Study officials:
affiliation: University Ghent
name: Barbara Cagnie, PhD
role: PRINCIPAL_INVESTIGATOR
References: