What is a Cumulative Trauma Injury?

Cumulative trauma injuries, also known as repetitive stress or repetitive motion injuries, occur from repeated actions or exposures that cause physical harm over an extended period. Unlike acute injuries, which result from a single incident, CT injuries develop slowly and can be difficult to pinpoint to a specific event or time.


Common Causes of Cumulative Trauma Injuries

CT injuries can result from a variety of repetitive activities or sustained conditions in the workplace, including:

Repetitive Motion:

  • Tasks that involve repetitive movements such as typing, assembly line work, or using tools that place continuous stress on specific body parts.
  • Examples: Carpal tunnel syndrome, tendinitis, and repetitive strain injuries.

Prolonged Postures:

  • Jobs that require maintaining the same posture for long periods, like sitting, standing, or bending, which can lead to musculoskeletal issues.
  • Examples: Lower back pain, neck strain, and shoulder pain.


  • Exposure to constant vibrations from operating machinery or equipment can contribute to CT injuries.
  • Examples: Hand-arm vibration syndrome, which affects nerves and circulation.

Continuous Pressure:

  • Work that involves sustained pressure on specific parts of the body, such as using hand tools or kneeling.
  • Examples: Pressure ulcers, bursitis, and neuropathies.

Environmental Factors:

  • Long-term exposure to noise, chemical agents, or poor ergonomic conditions can also lead to cumulative trauma.
  • Examples: Hearing loss from noise exposure, respiratory issues from chemical inhalation.

Identifying Cumulative Trauma Injuries

Recognizing CT injuries can be challenging due to their gradual onset. Key signs and symptoms include:

  • Persistent Pain: Ongoing discomfort or pain in the affected area that worsens with continued activity.
  • Swelling and Inflammation: Visible swelling or tenderness in the joints or muscles.
  • Reduced Functionality: Difficulty performing tasks that were previously manageable without discomfort.
  • Numbness or Tingling: Sensations of numbness, tingling, or weakness, particularly in the hands or fingers.

Filing a Workers' Compensation Claim for CT Injuries

If you believe you have a cumulative trauma injury related to your job, follow these steps to file a workers' compensation claim:

  1. Report the Injury: Notify your employer as soon as you recognize symptoms related to a CT injury. Early reporting is crucial for timely medical intervention and claim processing.
  2. Seek Medical Attention: Obtain an evaluation from a healthcare provider who can diagnose CT injuries. The medical provider will document your condition and its relation to your work activities.
  3. Complete a Claim Form: Fill out the workers' compensation claim form (DWC-1) provided by your employer. Detail your injury and the repetitive tasks or exposures contributing to it.
  4. Submit Documentation: Submit the claim form along with medical documentation to your employer or workers' compensation insurance carrier.
  5. Follow Up: Engage with your employer and the insurance carrier to ensure that your claim is processed and that you receive appropriate medical treatment and benefits.

Important Considerations

  • Cumulative Effect: CT injuries often involve multiple contributing factors. It’s essential to document all relevant work activities and exposures.
  • Apportionment: California workers' compensation law allows for apportionment, which means that benefits may be adjusted if pre-existing conditions or non-work-related activities contribute to the injury.
  • Legal Support: Due to the complexity of CT claims, consider consulting with a workers' compensation attorney to navigate the process effectively and secure the benefits you deserve.


For more detailed information on cumulative trauma injuries and filing a workers' compensation claim, please refer to:

  • California Department of Industrial Relations - Cumulative Trauma
  • California Workers' Compensation Institute - Cumulative Trauma
  • Guide to Workers' Compensation in California

This memo provides an informational guide to understanding Cumulative Trauma Injury under California's workers' compensation system and it is not intended as legal advice. For any specific legal advice or assistance, please contact our highly competent and knowledgeable attorneys.