Musculoskeletal disorders (MSDs) occur frequently in the workplace and in 2011 accounted for a third of all injuries and illnesses reported, according to the Bureau of Labor Statistics. These injuries result in time away from work and lost productivity, which significantly impact employers in addition to employees. In 2009, MSDs cost businesses in the U.S. $12.75 billion in direct costs (medical bills, workers’ compensation payments). That number doesn’t even include the indirect costs related to training new workers, damaged products or slowed production.
So what exactly are work-related musculoskeletal disorders (WMSDs) and what can employers do to prevent them?
These disorders, sometimes called repetitive motion injuries, overuse injuries or ergonomic injuries, often develop over time as the result of repeatedly working at awkward angles, straining muscles, lifting improperly, using incorrect tools and a number of other factors. Many of these factors are related to workplace posture, and postural problems commonly affect the back, shoulders, elbows, neck and wrists. WMSDs can impact muscles, tendons, cartilage, nerves, joints and spinal disks.
Employers can take steps to help identify problematic work movements and postures and to prevent WMSDs from occurring in the future. A recent report developed jointly by the National Institute for Occupational Safety and Health (NIOSH) and the Centre for Research Expertise for the Prevention of Musculoskeletal Disorders (CRE-MSD) explains the value of observing the postures of workers during their regular tasks to determine whether the current design of workplace procedures could lead to ergonomic problems. The report, called “Observation-Based Posture Assessment,” offers some helpful insights into the details of posture analysis that could benefit many workplaces.
Three Approaches to Posture Assessment
NIOSH explains that there are three main methods of posture assessment that workplaces can use.
The first is having workers report what they think the risk levels of their jobs are and what movements might be problematic. This method is the most cost-effective to implement, but can require providing workers with additional training and tends to be the least accurate method for assessing postures.
For workplaces that would like a more accurate measurement of potentially problematic postures, observation-based posture assessment is a good option. For this method, a company would have a trained analyst (like an ergonomist) assess postures in the workplace (either directly during the workday or from a video recording). This method, NIOSH says, requires some trial and error, but provides a good balance of data and cost.
The third method of gathering data about posture is direct measurement, which involves either a motion capture system or an electrogoniometer, a device that measures joint angles. This option offers the most precise data, but is also the most expensive assessment method to implement.
The NIOSH report takes a closer look at the second method—observation-based posture assessment—because it provides a balance of accuracy, cost and required expertise. Let’s look at some things to consider when using this method.
Observation-Based Posture Assessment
Whether you have a qualified person observe postures in real time or from a recording, this person will pay attention to parts of the body that are at risk (back, neck, shoulders, elbows, wrists), and look for whether postures are neutral or non-neutral. Neutral postures generally mean a part of the body is flexing or bending at a 30-degree angle or less. The higher the number of degrees a joint or body part bends, the more non-neutral it is. Predictably, the more non-neutral a posture is, the more likely is could cause injury over time. For example, if a worker has to repeatedly bend to floor-level to pick up boxes, this is more damaging than picking up boxes at waist height because the angle of flexion is greater.
These postures are the types of postures an employer will want to reduce or eliminate, but we’ll discuss how to do that in a minute. First, let’s examine additional recommendations for gathering data using observation-based assessment.
Tips for Recording Posture
Taking a video recording of postures in the workplace can lead to more accurate data about posture because the person(s) analyzing it will be able to review it multiple times and potentially from multiple angles. NIOSH recommends the following:
- Take footage from multiple views to provide the most comprehensive information.
- Zoom in on the body part in question so the angle of movement is more visible.
- Position the camera perpendicular to the joint in question. (For example, if you are trying to gather data about how workers bend their wrists, don’t film the wrist from the top; film it from the side.)
- Don’t move the camera more than necessary.
- Ask workers to not wear loose-fitting clothing so you can see joints clearly.
- Take footage of multiple workers performing the same task over a period of time.
These recommendations will ensure the video you take provides the best pictures of the postures used as possible.
Solving Postural Problems in the Workplace
One of the goals of ergonomics in the workplace is to make jobs fit the people doing them, not the other way around. Therefore, employers must find ways to adjust work procedures and workstations so employees face fewer tasks that require them to move in un-ergonomic ways.
After gathering data and having it assessed by an expert or qualified person, it’s time to take that information and see if the tasks that involve non-neutral postures can be changed. This might mean moving materials from one part of the warehouse to another, providing carts for moving materials, switching the kinds of hand tools used on a daily basis or changing where workers stand. The adjustments you make will obviously be specific to your workplace, so think about what changes make the most sense. The changes may also require an employer to adapt a task so it’s suitable for employees of different sizes. A task might be easy for a tall individual, but not a short one, or it might be easy for someone with a lot of upper body strength, but difficult for someone without it. Finding ways to make a task suitable for all of these workers is the challenge.
Other measures should be put in place as part of a workplace ergonomics problem, too. Employers should foster a culture of open communication and encourage workers to report symptoms as soon as they occur, according to OSHA. Many workers delay reporting symptoms until it’s too late to easily fix their health problems. Companies can also consult injury data—perhaps annually—to see if any patterns emerge in the types and locations of ergonomic injuries. By coupling this type of analysis with the analysis of postures, companies can get a better sense of what has happened and what is currently happening in the workplace. Understanding this information is key to preventing the development of future WMSDs.
For more information about ergonomic injuries and their associated costs, read our recent blog post about the topic.