Not everyone has heard of musculoskeletal disorders (MSDs) but almost everyone has been at risk of developing one. In fact, they are so common that they affect about one-third of the world’s population. MSDs, moreover, are the main cause of chronic disabilities, absence from work, reduced productivity, and lowered quality of life.
Not only are work-related musculoskeletal disorders prevalent, but they also represent a significant cost for employers. Research conducted by the Bureau of Labor Statistics confirmed that MSDs were the single largest category of workplace injuries, and were responsible for almost 33 percent of all workers’ compensation costs.
Facts About Musculoskeletal Conditions
According to the National Institute for Occupational Safety and Health (NIOSH), a musculoskeletal disorder is an injury to the muscles, tendons, ligaments, nerves, joints, cartilage, bones, or blood vessels located in the arms, legs, head, neck, or back.
MSDs are caused or aggravated by various physical tasks that are common in the workplace and in daily life, such as lifting, pushing, and pulling.
The symptoms of MSD include pain, stiffness, swelling, numbness, and a tingling sensation that can be uncomfortable or distracting.
According to the WHO:
- MSDs affect about 1.71 billion people worldwide
- An MSD significantly limits mobility and dexterity
- Among the various types of MSDs, low back pain causes the highest burden
- Disabilities related to MSDs are projected to continue increasing in the coming decades
Fortunately, musculoskeletal disorders are preventable. Employers and safety professionals can develop effective ergonomic programs to reduce the rate of MSD incidents in their workplaces.
Doing that, however, first requires an understanding of what these disorders are and which risk factors contribute to their development.
(Learn more in What Is Lean Ergonomics – And Why Does It Matter?)
1. Upper Limb Musculoskeletal Disorders
Upper limb MSDs can affect any region of the neck, shoulders, arms, wrists, and hands. The most common work-related upper limb musculoskeletal disorders are:
2. Low Back Musculoskeletal Disorders
Low back MSDs are associated with spinal disc problems, muscle injuries, and soft-tissue injuries. These disorders often arise from physical work that involves holding static and awkward postures, repetitive motion, and whole-body vibration.
3. Lower Limb Musculoskeletal Disorders
Lower limb MSDs affect the hips, knees, and legs. Workers whose jobs involve standing or kneeling for extended periods of time, repetitively kneeling or squatting, or jumping from a height are at greater risk of developing these.
The most common work-related lower limb musculoskeletal disorders are:
- Hip and Thigh: Osteoarthritis, Hamstring Strains, and Sacroiliac Joint Pain
- Knee and Lower Leg: Osteoarthritis, Bursitis, Pre-patellar Tendinitis, Shin Splints, Infra-patellar Tendinitis, and Stress Fractures
- Ankle and Foot: Achilles Tendinitis, Blisters, Foot Corns, Bunions, Hammer Toes, Sprained Ankle, Stress Fractures, and Varicose Veins
Risk Factors for Developing Musculoskeletal Disorders
The various risk factors that increase a worker’s likelihood of developing an MSD can be divided into three main categories:
1. Ergonomic Risk Factors
The major ergonomic risk factors include the following:
- Force: Force refers to the amount of physical effort a worker exerts when performing tasks that involve carrying, lifting, pulling, or pushing. The risk of injury increases if the amount of force required to perform the job exceeds the worker’s physical capacity.
- Repetitive Movement: Repeatedly using the same group of muscles to perform the same motion is another ergonomic hazard.
- Posture: Working for extended periods of time in positions that don’t conform to the body’s natural alignment puts stress on the body, which increases the risk for musculoskeletal disorders.
- Vibration: The vibrations from machinery, tools, and equipment transfer to anyone who is in direct contact with them. Repeated or prolonged instances of hand-arm vibration or whole-body vibration can affect the blood vessels, which can lead to MSDs.
2. Organizational and Psychosocial Risk Factors
Organizational and psychosocial risk factors include:
- Infrequent breaks
- Working under pressure or tight deadlines
- Poor job design
- High work demands
- Lack of support from colleagues and supervisors
- Job insecurity
While these don’t directly affect the muscles or soft tissue, they tend to result in behaviors that do.
These forms of psychological or emotional stress can cause workers to pay less attention to their bodies while they work, tense their muscles, or become less physically active overall. Those behavioral responses to stress place them at greater risk of developing MSDs.
3. Individual Risk Factors
Individual risk factors include:
- Age: As we age, our soft tissue becomes less capable of withstanding the stress placed on it. Likewise, muscle strength tends to diminish.
- Gender: Research has shown that the prevalence of work-related MSDs is higher among women. This could be because women are typically employed in tasks involving a combination of biomechanical and psychosocial risk factors. The fact that women tend to carry out a majority of the housework and childcare also puts a greater strain on them and impedes their ability to rest between work shifts.
- Health and Lifestyle: Smoking, alcohol consumption, and obesity have also been linked with a greater risk of developing MSDs.
The Three-Level Prevention Strategy
According to the European Agency for Health and Safety at Work, preventive strategies for musculoskeletal disorders should be taken at three levels:
- Primary prevention concerns the risk assessment process and the implementation of technical, organizational, and person-oriented hazard control measures
- Secondary prevention involves early identification and intervention
- Tertiary prevention aims to facilitate the return-to-work process for workers who have suffered a musculoskeletal injury
Given the various types of risk factors that contribute to these common hazards, keeping workers safe from MSDs will require a holistic approach that targets a number of variables, from proper posture to stress management.