Repetitive Motion & Overexertion Injuries Expert Article

Occupational Ergonomics is the dominant field of study that relates demands on the musculoskeletal system to the design of the workplace. Within industry, ergonomists focus on the stressors exerted on workers when performing their day-to-day work duties. As such, an ergonomist can be a logical choice as a testifying expert in certain workplace injury disputes. 

In this article, Ergonomics & Industrial Hygiene Expert, Diane Trainor, Ph.D., discusses musculoskeletal injuries in the workplace setting. She covers repetitive movement hazards associated with handling materials, and preventative strategies that are often relevant to workplace injury litigation.

Movement Hazards & Manual Materials Handling

Manual materials handling is the process of routinely moving and handling objects by carrying, holding, lifting, pulling, pushing, and stooping. Manual materials handling tasks likely expose workers to movement hazards, particularly if these tasks are performed repeatedly or over long workplace time periods. If this results, the risk of a worker experiencing fatigue and injury increases.

The main workplace conditions (risk factors) associated with the development of injuries in manual materials handling tasks include:

• Awkward Postures – bending, twisting
• Repetitive Motion – frequent reaching, lifting, carrying
• Forceful Exertions – carrying or lifting
• Pressure Points – grasping loads, leaning against hard or sharp parts, surfaces, or edges
• Static Postures – maintain a fixed posture for long periods of time 

Materials handling is likely to create workplace hazards if it involves repeated, sustained, high force impacts, sustained awkward work postures, and/or moving heavy loads. 

• Repetitive movements can result in the development of carpal tunnel syndrome, commonly found in workplaces that utilize computers. 
• Exposure to sustained vibrations are likely to create a dangerous condition for jackhammer operators. 
• Warehouse workers required to lift and move heavy, unbalanced, or hard to hold loads have a likelihood to experience back injuries, trips, and/or falls. 
• Workers required to lift their arms with their shoulders over their heads are likely to sustain soft tissue injuries to the shoulders, neck, and upper arms. 

A combination of these forces, postures, movements and or vibrations further increases the risk of injury. For instance, twisting at the waist while lifting can cause a shearing motion on the lumbar spine, resulting in lower back injury. These activities are performed by workers in many trades, including warehouse staff, miners, electricians, mechanics, and general laborers.

Standards of Care for Ergonomics in the Workplace   

Not every workplace injury involving sitting, moving, and lifting can be predicted or prevented. Evidence-based studies and workplace design, however, demonstrate that a workplace risk assessment is predictive in identifying which motions and/or job actions pose a greater risk for musculoskeletal injury.

Implementation of measures to prevent or reduce the risk associated with these injuries are more likely than not to mitigate the dangerous workplace condition and help to maintain a safe and productive workplace.

The assessment and analysis of injury in the workplace may include investigation into one or more of the following:

• Workplace design
• Employee training
• Posture assessment at workplaces
• Flexibility of workstation orientations
• The repetitive nature of a task
• The need to lift and move heavy objects
• The need to assume awkward postures during manual handling of objects
• Presence of excessive vibration
• Forceful exertions
• Repeated or sustained awkward postures
• Incorrect lifting or stacking of work-related objects

Workplace Ergonomics Expert Witness Investigations

The presence of ergonomic hazards and other risk factors in the workplace increases the likelihood of injury and may require specific safety interventions. The investigation of these incidents will typically consider the various factors that are a cause of an injury to occur, whether these factors were foreseeable to those responsible for worker safety, and ultimately if appropriate prudent precautions were taken to provide a reasonably safe and healthy workplace environment. 

Through the effective development of ergonomically designed workplace procedures, it is predictive that incidence and severity of industry-related musculoskeletal injuries are likely to be reduced. The ergonomics experts at Robson Forensic are frequently retained to investigate disputes involving the adequacy of workplace policy and designs that help keep workers safe and at a reduced risk for injuries.

For more information, submit an inquiry or call us at 800.813.6736.

Featured Expert

Diane Trainor, Ph.D., CHCM

Certified Hazard Control Manager & Workplace Safety Expert

Dr. Trainor is an expert in the fields of Environmental and Occupational Safety and Health and Occupational Ergonomics. Her casework frequently involves investigations into workplace mishaps,… read more.