New Study Points to Ways Loggers Can Minimize Knee, Back, and Shoulder Injuries

By Lindsay Mohlere

This fall, a new manual of best practices focused on preventable injuries in the logging industry is available through the Washington State Department of Labor and Industries (L&I).

Dr. Patee follows Josh Chilton down the hill in a rigging test.

SHIP Grant

Over a year ago, the Washington L&I offered a Safety and Health Investment Projects (SHIP) grant commissioning the study to research, test, and develop the manual to help prevent and reduce musculoskeletal injuries, which account for the largest percentage of compensable occupational claims within the logging industry.

The SHIP grant was awarded to a collaborative group that includes Chilton Logging of Woodland Washington; DorsaVI, an Australian wearable technology analytic firm; and Work Right NW, a company that pairs medical experts with corporations to focus their efforts on injury prevention.

The team was led by Dr. Nic Patee, Doctor of Physical Therapy (DPT), the founder and president of Work Right NW. Patee worked in the woods as a rigging man setting chokers, pulling rigging, and chasing during the summers while in college. This intimate knowledge of the industry was invaluable in creating the study.

Live sensors are illustrated on a laptop.

A Dangerous Profession

“Logging is the most dangerous profession in the continental U.S.,” Dr. Patee said. “It has the highest fatality rate, the highest incident rate, highest risk of disability rate — all of those things. However, in most industries, we wouldn’t expect people to get injured. We would work hard to prevent this from happening. But because loggers have this culture and long-standing pride of being hard-working people, it isn’t approached that way. What we have is very few loggers over the age of 50 years old able to work out in the brush because they’re too broken down. That’s not acceptable. We should be looking for ways to improve that.”

Dr. Patee explained that chronic development of musculoskeletal issues like knee pain, shoulder pain, and back pain take most loggers out and prevent them from doing their jobs.

Dr. Patee monitors rigging test with on-site narration and video.

To find ways to help minimize the risks and develop best practices, Dr. Patee’s group spent more than 15 months assessing 20 different projects where they hooked up wearable tech sensors to loggers to create a data profile of the demands of the job. A team of 17 loggers from Chilton Logging volunteered for the projects. Work Right NW assigned three physical therapists and a professional ergonomist along with a team of data analysts from DorsaVI to participate in the SHIP grant study.

The Process

To determine which areas of the logging profession to focus on, the Work Right team looked to particular logging jobs where musculoskeletal issues were prevalent. Rigging men, timber cutters, and equipment operators had most of these issues.

Using DorsaVI patented ViSafe technology, the team developed baseline assessments as a guide to understanding the problems of each job. Volunteers were fitted with ViSafe stick-on censors that accurately mapped movement, muscle activity, and vibration. They are a medical grade solution with FDA and TGA approval and the CE mark.

The wearable technology analyzes movement across three planes of movement and captures EMG data to quantify the physical demands of a job on a worker. Additionally, it tracks at 200 frames per second and pairs the data with real-time video of the job.

At the end of the data collection process, the raw numbers were analyzed by DorsaVI and sent back to Work Right NW. In a workshop setting, the management team of Chilton Logging, an ergonomist, and Work Right staff talked through the information and brainstormed ways to solve the problems and then recommended interventions. After the proposed solutions were tested, a comparison of data highlighted the methods and results. The interventions were evaluated to ensure benefit to the workforce in the true work environment.

The Recommended Best Practices

While the study covered a wide range of tasks and identified several areas of risk, it was not able to develop best practices for all. The following are the study’s conclusions.

Equipment Operator

• Problem: Neck and shoulder pain from slouching forward while running equipment.
• Best Practice: A properly fitted 5-point harness instead of the traditional lap seat belt. Proper fit means a snug harness that keeps the shoulders straight.
• Problem: Fatigue and discomfort associated with the “bobble-head” movement occurring because the seats are usually bolted directly to the machine’s frame.
• Best Practice: Integrate custom bolts to connect the seat to the mainframe to reduce the impact of whole body vibration.

Rigging Men

• Problem: Consistent (nearly constant) risk factors for choker setters’ dominant shoulder from pulling chokers with one hand behind the back. Identify a method that places less stress on the shoulders.
• Best Practice: Pulling chokers over the shoulder demonstrated significantly less risk.
• Problem: Determine which equipment is best for a hook tender to reduce effect and effort while pulling haywire.
• Best Practice: Hindu eye haywire, as opposed to spliced eye, had significantly less EMG activity in both back and shoulder. Hindu eye cable also snagged less in the brush.
• Problem: Reduce shoulder impact risk while pulling haywire up or down hill.
• Best Practice: Use a lightweight climbing harness to centralize the pull of haywire and reduce the impact on shoulder and lumbar spine.
• Problem: Blocks and coils are two of the heaviest tools carried in the brush. Reduce the risk of injury and the variability of an unstable load.
• Best Practice: Use a lightweight backpack for transporting gear. It will reduce the physical impact on back and shoulders.

Dr. Patee centers the DorsaVI movement sensor on lower back.

A Two-fold Purpose

“Logging is a dangerous job, and it’s struggling to get workers,” Dr. Patee said. “If we can understand how to extend the working life of the logger, that would help multiple ways. Not only by reducing injuries, but also impact the industry by keeping people working in the industry longer.”

The complete study, Best Practice/Train the Trainer, is available through the Washington State Labor and Industries Board at http://www.lni.wa.gov/Safety/Topics/AtoZ/Logging/resources.asp.