Avoiding a Mouse-related Musculoskeletal Injury

By Ryan Fogel,

Repetitive Stress Injury (RSI) is a kind of catch all phrase for many conditions, including:

  • Carpal Tunnel Syndrome
  • Tenosynovitis / DeQuervain’s Syndrome
  • Tendonitis
  • Thoracic Outlet Syndrome
  • Trigger Finger
  • Myofascial Pain Syndrome
  • Chronic Sprain / Strain

Repetitive Stress Injuries occur from repetitive movements involving a specific set of muscles and joints. Mechanical Onset RSI (MORSI), also known as mouse arm disease (MAD), is a mouse-related musculoskeletal injury that affects millions of people around the world and costs employers and insurers billions of dollars. As we spend increasing amounts of time at our computer workstations, we need to be aware of how the design and arrangement of our equipment can impact our chances of acquiring a mouse-related musculoskeletal injury.

How Do I Avoid a Mouse-Related Musculoskeletal Injury?

The feature photo above is an excellent example of how NOT to use your mouse. The following tips should help you avoid a mouse-related musculoskeletal injury. These same posture principles apply to other input devices (e.g., trackball, touchpad, pen, digitizing puck etc.). Postural variation is a key factor for good ergonomics. Try to regularly vary your posture when you work with a mouse, and in this way you will help to minimize the risk of ergonomic problems. Remember, the best ergonomic mice are designed to allow you to vary your posture while working with the mouse.

  1. Mouse GripHold the mouse gently when moving it over a mousing surface. Cup your hand over the mouse, almost floating, without allowing the mouse to support the weight of your arm. Gripping the mouse tightly will strain the muscles in your arm and hand, which could lead to a mouse-related musculoskeletal injury. Frequent breaks should also be taken and arms stretched to boost circulation and re-oxygenate the hand and finger muscles.
  2. Mouse from the Elbow – The human wrist was not designed for a computer mouse. Operating a mouse is awkward and becomes uncomfortable, because the wrist is turned up to 90 degrees from its most comfortable natural resting position. Any bending of the wrist, either to the side or up and down, can lead to tendon damage or other mouse-related musculoskeletal injury. To help avoid a mouse-related musculoskeletal injury, make controlled mouse movements with the entire lower arm, using your elbow as the pivot point and keep your wrist straight and neutral.
  3. Optimal Mouse Position – The most up-to-date studies show that a slightly reclined sitting posture with the hips flexed at 100 to 115 degrees is ideal if you have to sit at a desk. So, sit back in your chair, relax your arms then lift your mousing hand up, pivoting at the elbow, until your hand is just above elbow level. Your mouse should be positioned somewhere around this point. Don’t use a mouse by stretching to the desk or out to the side of a keyboard. This stresses your back by reducing the angle of your hips and increases your chance of getting a mouse-related musculoskeletal injury.
  4. Protect Your Wrist – Your wrists should never be in direct contact with any surface, including wrist rests and mouse pads. Instead, use the base of your palms to support the weight of your hands and arms in between mousing and typing to keep pressure off the sensitive carpal tunnel area in the wrist. This will help reduce the risk of a mouse-related musculoskeletal injury.
  5. Avoid Restricting Circulation – Blood circulation is responsible for the action that moves nutrients, gases and wastes to and from cells, and helps stabilize body temperature and pH to maintain harmony. When blood vessels constrict, blood does not flow properly. Many people have exposed blood vessels near the skin at the wrist, where the pulse is often taken. Any pressure in this region will disrupt circulation into the hand and this will cause constriction in those blood vessels, which can cause hands and fingertips in the mouse hand to become cold. This can lead to a mouse-related musculoskeletal injury like Carpal Tunnel Syndrome, Arthritis, Raynaud’s, DeQuervain’s, or Tendonitis.
  6. Don’t Use a Wrist Rest – Don’t use wrist rests or splints while typing, experts warn. Research has shown that using a wrist rest doubles the pressure inside the carpal tunnel. According to Professor Alan Hedge, Cornel University, the floor of the tunnel is a more flexible ligament that transmits external pressure changes directly into the carpal tunnel. Are you already suffering from Carpal Tunnel Syndrome (CTS)? One way to find out is by performing a test called “Tinel’s sign”, which simply involves tapping on the palmar surface of the wrist, which is enough to cause tingling and numbness in someone developing CTS.
  7. Avoid Restricting Arm Movement – With a softly padded wrist rest, especially one that is rounded, or a soft chair arm rest the forearm becomes “locked” into position. Mouse movements should be made using the elbow as the pivot point, not the wrist. Too much wrist movement increases intracarpal pressure, leading to a mouse-related musculoskeletal injury.
  8. Mouse Shape – Choose a mouse design that fits your hand, but is as flat as possible to reduce wrist extension. Don’t use a curved mouse. Use a larger, symmetrically shaped mouse, such as the Whale mouse or the Perfit mouse, which encourage arm rather than wrist movements or that encourage postural variety and one or two-handed use. Pen-based mice designs also allow a more comfortable grip. Some types of mouse palm support can be attached to the mouse, such as the Mouse Bean.
  9. Load sharing – If you want to load share between your right and left hands, using the mouse for some of the time with each hand, you need to choose a mouse platform that can easily be configured to the left and/or right and a symmetrical shaped mouse that can be used by either hand.

Other Input Devices

Whether you choose a different mouse design, trackball, joystick, pen, touchpad, multitouch pad, or some other input device, make sure that you position it comfortably and that your wrist stays in a neutral position when using the device to avoid a mouse-related musculoskeletal injury.

How to Position Your Mouse in Your Workspace

Right-handed and left-handed mouse users should position a flat mouse platform, 1-2″ above the keyboard and over the numeric keypad – you can easily move it out of the way if you need to access these keys. With a downward sloping mouse platform, position this close to the side of the keyboard so that you can use the mouse in a neutral wrist position. However, if you are left-handed and have a right-handed keyboard, with the numeric keypad on the right, your best bet would be to use an angle-adjustable mouse platform placed immediately to the left side of the keyboard, and position it so that your left wrist is neutral. Mouse platforms are commercially available. If you require assistance choosing a mouse platform, please call Accredited Rehabilitation Consultants.

Accredited Rehabilitation Consultants not only provides ergonomic evaluations and ergonomic consulting, we also can help you get set up with the ergonomic equipment you need to prevent costly injuries in the workplace. See our Ergonomic Equipment page for more information on how we can help you make appropriate ergonomic selections for your workplace. We have relationships with many manufacturers and will recommend the best options regarding ergonomic equipment on the market.

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  Filed under: Ergonomic Injury, Ergonomic Injury Prevention, Workplace Injury Reduction
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Looking for an Ergonomics Consultant in Los Angeles?

By Ryan Fogel,

The term ergonomics is derived from the Greek words ergon [work] and nomos [natural laws]. It is concerned with the “fit” between the user, equipment and their environments. Ergonomics at work takes account of the user’s capabilities and limitations in seeking to ensure that tasks, functions, information and the environment suit each user. Ergonomic design is the application of ergonomic knowledge to the design of the workplace (i.e., work tasks, equipment, environment) for safe and efficient use by workers. Good ergonomic design makes the most efficient use of worker capabilities while ensuring that job demands do not exceed those capabilities.

How can ergonomics in the workplace and human factors improve workers’ health and safety?

Practicing ergonomics at the workplace and considering human factors can:

  • Reduce the potential for accidents, workers’ compensation and healthcare costs by reducing ergonomic risk factors;
  • Improve performance and productivity with work environments that are designed to allow for good posture, less exertion, fewer motion and better heights and reaches;
  • Improve work quality and morale by reducing the potential for fatigue and discomfort.

What is an ergonomics consultant?

An ergonomics consultant in Los Angeles and other areas, is one who helps companies by identifying ergonomic issues in the workplace and corrects those conditions or recommends changes to improve the client’s work environment or working conditions for the purpose of preventing injuries and improving the workers’ wellbeing and prevent injuries.

Ergonomist consultants participate in the design of systems to optimize overall system performance. A system is comprised of devices, tools, technologies, environments and/or organizational structures with which people interact to accomplish defined objectives. They also contribute to the design and evaluation of tasks, jobs, products, environments and systems in order to make them compatible with the needs, abilities and limitations of people.

Take a Break!

Did you know that frequent breaks could help lower the exposure to ergonomic injury risk?

The human body is always in movement while performing tasks. Even while seated, postural muscles are exerting tension to hold our upper body and head upright. Prolonged muscle exertion can cause fatigue, which may lead to an ergonomic injury.

Rest is a key component in preventing musculoskeletal injuries. Here are some ways you can take a break without disrupting your productivity:

  • Move your printer somewhere that requires you to stand and walk to get your printout.
  • Stand up while on the phone.
  • Break up continuous computer time with checking phone messages, making phone calls to clients, etc.
  • During your 10 to 15 minute and lunch breaks, get away from the desk and use the time to take a walk or other enjoyable activity.

Like other health care fields, the ergonomics consulting field has a variety of specialties, including:

  • Ergonomics Safety Consultant
  • Work Ergonomics Specialist
  • Office Ergonomics Consultant
  • Certified Ergonomics Assessment Specialist
  • Certified Professional Ergonomist

Ergonomic consultants perform such ergonomic design services as:

  • Industrial Ergonomic Design
  • Office Ergonomics Design
  • Ergonomic Workplace Assessment
  • Ergonomic Workstation Assessment
  • Ergonomics Training

What are ergonomic injuries?

Ergonomic injuries are injuries caused by ergonomic risk factors relating to high task repetition, performing job duties that cause the worker to assume repetitive/sustained awkward postures, unsafe/dangerous equipment and other factors that can result in workplace injuries. OSHA often uses the term Musculoskeletal Disorders (MSDs) to define ergonomic injuries. However, ergonomic injuries can also be defined as Repetitive Stress Injuries (RSIs), Repetitive Motion Injuries (RMIs), Cumulative Trauma Disorders (CTDs), or Cumulative Trauma Injuries (CTIs). Work related MSDs (including those of the neck, upper extremities and low back) are among the leading causes of lost workday injury and illness. According to the U.S. Bureau of Labor Statistics, work-related musculoskeletal injuries cost American businesses $15 to $20 billion each year in workers’ compensation costs alone.
Looking for an Ergonomics Consultant in Los Angeles
Why is an ergonomic assessment important?

  • An ergonomic assessment by a certified ergonomics assessment specialist will reduce injuries and illnesses, which affect insurance premiums, legal expenses, employee productivity, attendance, compensation and medical costs.
  • Ergonomic assessments reduce stress and fatigue, resulting in greater efficiency and a better way of life for all employees.
  • An ergonomics assessment by top ergonomics specialists in Los Angeles will assist in assuring regulatory compliance by providing employees with a safe and productive work environment, free from recognized hazards.
  • A comprehensive ergonomic assessment benefits the worker by improving efficiencies and comfort while maximizing safety at a justifiable cost.

What does an ergonomic assessment from a certified ergonomics assessment specialist include?

Ergonomic assessments take many human factors into consideration, including:

  • Job task and its demands on the worker (physically, mentally, emotionally)
  • Equipment used (size, shape, weight, etc.) and appropriateness for the task
  • Task-related information and how it is presented, accessed, used and changed
  • Physical environment factors such as noise, temperature, humidity, vibration, lighting, etc.
  • Culture and social environment factors such as team work, proximity of co-workers, management attitudes and support, etc.
  • Worker physical aspects such as height, weight, fitness, strength, sensory acuity (i.e., vision, smell, hearing, touch) and potential for stress and strain on muscles, joints and nerves
  • Psychological factors such as mental abilities, personality, knowledge, work experience

Once the assessment is completed, the certified ergonomics assessment specialist will either implement or help implement:

  • On-site workplace ergonomics seminars for employees, supervisors and managers, ergonomic equipment recommendations and installations
  • Ergonomics program development (designed to address the specific needs of the client company)

What is an ergonomic risk assessment?

The ergonomic risk assessment is an examination of the aspects of a task that may expose workers to an increased risk of injury. A hazard is something that has the potential to cause harm. Risk identifies the likelihood that the harm will be done and details the severity. The risk assessment determines if enough has been done to control the risk or if any further measures need to be taken to reduce the risk

What does an ergonomic design consultant do?

An ergonomic design consultant evaluates the workplace, the workspace and the tasks an employee must accomplish as part of an ergonomics assessment. After making these observations, the consultant with then apply their knowledge about human abilities, limitations, and other characteristics to make recommendations that are relevant to the design of tools, machines, systems, tasks, jobs and environments for safe, comfortable and effective human use.

What does an office ergonomics consultant do?

Office Ergonomics is the branch of ergonomics dealing specifically with the office environment. Office ergonomics consultants provide many services to help make the office environment healthy and safe for workers. Services include:

  • In-depth analyses of the set-up and design of all workstation components, work tasks, and postures adopted, which are typically provided when an employee is working in discomfort, is returning to work from an injury, and/or has a requirement for a job accommodation.
  • Generating an ergonomics evaluation report that provides recommendations to reduce any risk factors that may be contributing to the worker’s discomfort.
  • Helping workers understand how to set-up and adjust their existing workstation components while also identifying areas of concern and opportunities for improvement to reduce discomfort and improve performance.
  • Teaching workers basic office ergonomics, which can include teaching workers about office ergonomics hazards and teaching them proper work postures.

What does an ergonomic safety consultant do?

An ergonomic safety consultant plans and conducts projects and programs to ensure compliance with federal, state and local safety and health statutes and regulations. They conduct safety and health related investigations and provide consultative direction to managers and supervisors for actions and decisions. Additionally, ergonomic safety consults provide compliance based training and they recognize, monitor and make recommendations to ensure workplace safety hazards are corrected, through audits, ergonomic assessments and interventions.

What does a work ergonomics specialist do?

A work ergonomic specialist performs OSHA-compliant ergonomics analysis applicable in the industrial, healthcare, and office workplace to identify potential hazards that contribute to occurrences of musculoskeletal disorders. They also implement or assist with the implementation of cost-effective, high-impact solutions for workplace injury prevention.

The Best Ergonomic Consultants in Los Angeles

Accredited Rehabilitation Consultants, Board Certified Professional Ergonomists, identify ergonomic risks and offers solutions to reduce these risk factors and eliminate ergonomic injuries. We conduct comprehensive worksite assessments, analyze ergonomic variables in disability case management in order to develop individualized high impact solutions and workspace improvements.

Our goal is to create a Culture of Safety and Responsibility for effective and sustainable health, wellness, safety, comfort, and production in the workplace. We take a four-phased approach with our ergonomic consulting evaluation services:

Applied Rehabilitation Consultants also provides:

  • Injury Prevention Education – Employee training on reducing and preventing workplace injuries.
  • Expert Witness Services – Expert consultation, opinions, reports and testimony for litigation.
  • Job Analysis – Independent (unbiased) modified and alternative position job analysis.
  • Ergonomic Equipment – providing a variety of ergonomic furniture and accessories such as ergonomic chairs, articulating keyboard trays, lighting, monitor arms and more.

For more information about our services and ergonomic equipment, please call 323.930.6599.

Resource: http://www.asse.org/practicespecialties/ergonomics/

  Filed under: Ergonomics Consulting, Workplace Injury Reduction
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