OFFICE ERGONOMICS

The purpose of the visits to the worksite was to determine the physical demands of the pre-injury job duties and provide an opinion on whether the job demands exceed the precautions for the worker’s bilateral wrist injury.
ABC Company recently purchased new workstations for two employees one of the employee’s voiced some new concerns. The employee has been experiencing ongoing right elbow and right wrist pain. The employee indicated that they were receiving physiotherapy treatments for their discomfort. The employee reported experiencing mid back discomfort since their return to work from a short absence due to illness and began using the new workstation. The purpose of this evaluation was to review the workstation, determine any areas of concern and provide recommendations.
The new workstation is adjustable in 1/2” increments. The employee performs most of their tasks on the computer working on computer software with clicking and manipulating the mouse. The employee reviews plot sheets and writes notes on the sheets and makes necessary changes on the computer. Setting the proper desk height and keyboard height are key elements to avoiding non-neutral postures of the back, shoulders, neck, arms and wrists.
The desk was set at the employees optimal work height. End-user orientation was completed to demonstrate the use of the articulating keyboard tray. It was determined that the tray height was positioned too high which promoted increased elevation in the shoulders. At this time, the tray was adjusted to improve these working postures.
The employee is currently on modified restrictions, directed by his family physician, to avoid all mouse use with their right hand. The employee is now performing mouse tasks with their left hand, although at a much slower pace, to give their right hand a break. It was discussed that the amount of deviation created by placing the mouse to the right of the keyboard in comparison when moved to the left. Mousing on the left significantly improves mousing postures by reducing the reach over the number pad. The other point to note is the employee’s shoulder span in relation to his keyboard. Again, there is deviation to the radial side, when typing.
At the employee’s workstations where work is done with one arm for long periods of time, it is recommended that the forearm should be supported by the desk or adjustable armrests on the chair. The employee is in better postures when the keyboard tray is recessed and dropped one inch to accommodate the height of the keyboard. Therefore, modifications should be made to accommodate proper support in the chairs’ armrests. The arm rests need to be longer and have the ability to swivel in towards the body. This will lessen the load on their shoulders.
The essential tools used by the employee throughout their work day included the monitor. At times, the employee reads notes that they have created and was observed inputting the information into the computer. The employee picked up the paper multiple times to view the print at a closer view. This involved fully extending his right arm. The employee confirmed that this particular task is not required on a regular basis. However, explained that the reason for picking the paper up to view it closer was due to poor vision. The employee was also noticeably straining to view keys on his keyboard and print on their monitor. The employee admitted that they need to have their eyesight reviewed. These observations would help to explain some reasoning for their mid back discomfort due to bending forward, reaching with an outstretched arm.
During the observation, attempts were made to adjust the office chair. The goal was to better facilitate the employee sitting in the chair with comfortable postures of their spine, supported by the seat back. It was discovered that the lumbar support on the back of the chair was too low for their anthropometrics. The back height was adjusted to suit their needs. The arms on the chair were located at the edge of their elbow. Not enough support for them to make use of the arms.
As a follow up, the recommendations made to the employee and manager was: 1. Adjustable keyboard. This will help to position wrists in a neutral posture. This keyboard does not incorporate a number pad so it will significantly improve mousing postures by reducing the reach. 2. Chair – with extra deep seat and swivel arms. The employee will benefit from more support in the seat pan of their chair (seat pan depth) and arm support. 3. Document holder – one monitor riser. The document holder will be placed in front of the monitor to keep the employees view in neutral postures. 4. Mouse options – Alternating between the left hand and right hand is a great way to reduce the overuse of the wrist that contributes to discomfort and injury. Another option is to work with different styles of mousing devices. This will help to alter forearm postures and wrist movements. Employee has had previous assessments and treatment for symptoms of right sided elbow and finger tendonitis and tenosynovitis. During their recovery, they performed their duties with the left arm until symptoms started in the left elbow and finger. At present the employee is completing their work sharing between the left and right hands. This evaluation was conducted to determine if any further intervention would assist the employee in their recovery and prevent exacerbation of symptoms.

The employee was situated at a 30 inch high corner workstation with a height adjustable keyboard tray. Their monitor was located directly in front of their sight line with the height and distance within CSA guidelines. An angled document holder was located between the keyboard and monitor. Their chair was fully adjustable and appropriate for their anthropometrics. The adjustable armrest allowed the arm to be supported with appropriate wrist and forearm angles.
Figure 1.1 Workstation Layout

The employee estimates that they spend the majority of their working time seated performing a combination of mouse and keyboard operations in a programmer. Movement of the mouse is accompanied by a significant amount of mouse clicks. The employee has developed a number of techniques to facilitate their condition including learning to mouse with either hand and using a combination of keyboard commands in compliment with mouse driven operations. Previous assessments have addressed most of the furniture issues. Several types of mice have been trialed with minimal success.

Overall, the employee appears to be in good postures for most of the activities being performed. Their wrist angles, support for the low back and shoulder movements are well within CSA guidelines. The employee advises that they changed keyboard heights and made attempts to change postures every two hours. It was suggested to the employee that an attempt to have mini-breaks every 30-45 minutes would be more appropriate. The mini-break could be to obtain items that are typically in easy to reach zones. The mini-break is well founded in research and found to actually increase production in the long run. The employee should also be encouraged to receive physiotherapy treatment for their discomfort. The goal of treatment would be to decrease discomfort and increase blood flow to the affected areas. Otherwise there appears to be no equipment necessary to improve their current workstation setup.
To conclude the recommendations to the employee are to encourage continuously using both hands when performing a combination of mousing and keyboard activities rather than rely on single arm movements. There does not appear to be additional equipment necessary to improve their current workstation setup. Second, it was suggested that the employee make an attempt to have mini-breaks every 30-45 minutes. The mini-break could be to obtain items that were typically in easy to reach zones. Third, the employee should also be encouraged to receive physiotherapy treatment for their discomfort. The goal of treatment would be to decrease discomfort and increase blood flow to the affected areas.

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[ 1 ]. Ministry of Labour Office Ergonomics Guidelines http://www.labour.gov.on.ca/english/hs/
[ 2 ]. CSA guidelines http://ohs.csa.ca/standards/index.asp
[ 3 ]. CSA guidelines http://ohs.csa.ca/standards/index.asp