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Blueberry rakers' tendinitis.
Tanaka S; Estill CF; Shannon SC
N Engl J Med 1994 Aug; 331(8):552
A survey was conducted in August 1993 in an effort to determine the incidence of tendinitis among blueberry rakers in Maine. Questionnaires were distributed regarding symptoms. Physical examinations were conducted of the hands and wrists and an ergonomic assessment was undertaken of the process of raking. The study participants included 134 rakers, 73% of whom were men. The median age of the subjects was 30 years. Children, aged 12 to 18 years, accounted for 10% of the study population. Moderate to severe pain in the back was reported by 13.5% of the rakers, in the hand or wrist by 12.0%, and in the elbow by 7.5%. On physical examination, 9.8% had some hand or wrist pain, with a positive Phalen's or Tinel's test suggestive of carpal tunnel syndrome, or a positive Finkelstein's test suggesting de Quervain's disease. Rakers worked mostly in a stooped posture and frequently carried loaded buckets of up to 13 kilograms each. The typical motion involved a constant firm grip on the handle, with ulnar deviation of the wrist initially to insert the tines into the bush, followed by radial deviation and lifting of the rake to separate the berries. The motion was repeated 32+/-13 times per minute and the mean force of the lifting motion was estimated to be 87+/-17.5 newtons. The authors recommend that the wrist be kept in a neutral position to avoid deviations and that raking be done slowly during the initial work period to reduce the incidence of tendinitis. Efforts to design a better rake are also underway.
Musculoskeletal-system-disorders; Human-factors-engineering; Muscle-stress; Agricultural-workers; Ergonomics; Cumulative-trauma-disorders; Physical-stress; Tools
Issue of Publication
New England Journal of Medicine
Page last reviewed: October 5, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division