A recent study involving 89 commercial crab pot and gill net fishermen found an association between severe low back pain with:
- Running the puller or net reel (more than 50 percent of the work time)
- Sorting the catch on the boat (more than 50 percent of the work time)
- Unloading catch/supplies with or without mechanical assistance (more than 50 percent of the work time)
Also, an association was found between severe low back pain and increased mean percent time:
- Exposed to forces greater than 20 pounds in non-neutral trunk postures
- Performing tasks that generate greater than 3,400 N of spine compression
- Exceeding 3.0 Lifting Index as per the National Institute of Occupational Safety and Health Lifting Equation.
Severe low back pain was defined as low back symptoms that limited work (“reduced work level or tasks”) or interfered with fishing activity (“unable to work a day or more”).
At baseline, low back pain had been experienced by 61 percent of the subjects over the prior 12 months while severe low back pain was reported by 24 percent of the participants for the same time period. In follow-ups, the incidence of severe low back pain was reported by 26 percent of the fishermen (27 subjects/40 occurrences) that interrupted work for:
- 68 percent for a duration of 1 day
- 52 percent for a duration of 1 – 7 days
- 33 percent for a duration of 8 – 30 days
- 15 percent for a duration of over 30 days
The Bottom Line – How This Applies To Ergonomists
The prevalence of disabling low back pain among crab pot and gill net fishermen is considerable. This study identifies specific fishermen tasks that are related to the incidence of this disorder hence, pointing to where engineering/administrative controls should be focused.
Further, this study reinforces the value of select ergonomic tools (NIOSH Lifting Equation; Posture, Activity, Tools and Handling by Buchholz et al.) in revealing high risk tasks.
Other Key Points
Severe low back pain was experienced most by fishermen 18 to 29 years of age followed by those 40 years of age and older. Fishermen 30 to 39 had the lowest rate of severe low back pain.
Severe low back pain was also associated with:
- Fishing full time
- Working on another fisherman’s boat
- Performing fishing activities other than crab or finfish
- History of severe low back pain
Although done for more than 50 percent of the work time, the following tasks were not associated with severe low back pain:
- Driving the boat
- Loading bait and supplies with or without mechanical assistance
- Emptying or setting gear
- Cleaning the boat
- Maintenance work
Years of fishing experience were protective for experiencing severe low back pain.
The group studied was composed of southeastern US fishermen who worked commercially along coastal or inland waterways for small, independent employers.
The study was conducted among workers between 18-65 years of age who fished at least 20 hours per week for at least 6 months per year.
Self administered surveys were completed by subjects at baseline and 6-month intervals for up to two years which collected information on musculoskeletal pain, injuries, fishing activity and other exposures. Telephone interviews were conducted every 1 to 2 weeks during this time period gathering similar data. A telephone Supplemental Questionnaire was administered at the end of the study to elicit information relative to fishing tasks and non-fishing activity.
This position paper can be acquired at: http://www3.interscience.wiley.com/journal/121639185/abstract
Article Title: Ergonomic Risk Factors for Low Back Pain in North Carolina Crab Pot and Gill Net Commercial Fishermen
Publication: American Journal of Industrial Medicine, 52:311-321, 2009
Authors: K L Kucera, D Loomis, H J Lipscomb, S W Marshall, G A Mirka, and J L Daniels
This article originally appeared in The Ergonomics Report™ on 2009-05-06.