Elements of Ergonomics Programs A Primer Based on Workplace Evaluations of Musculoskeletal Disorders

NIOSH was asked to evaluate the incidence of upper limb disorders among workers engaged in sewing tasks at a uniform manufacturing company. The request was prompted by employee complaints that included aching, numbness, clumsiness, and swelling of the wrists and hands. OSHA log data were nonexistent in this plant at the time of this 1983 investigation. A medical questionnaire was specially designed to gather data on upper limb symptoms, with particular emphasis on hand/wrist problems. Sections of the questionnaire covered the usual background information (age, sex, occupational history), the present job at the plant, the nature of hand motions (lifting and lowering, pushing and pulling, twisting and turning, screwing, bending and rotating wrists, pinching and grasping with fingers), pain and discomfort areas (neck, shoulders, arms, elbows), the nature of symptoms in hands or wrists (swelling, stiffness, cramping burning, tingling), the time of onset (late night awakenings), and any difficulties with hands and fingers in some everyday tasks (e.g., buttoning shirt, turning key in lock or doorknob, holding tools) plus medical history asking about any injury, surgery, or pre-existing diagnostic problem (e.g., arthritis) that could account for apparent problems. A section of the questionnaire also included a picture of both surfaces of the right and left hands with the instruction to shade in those areas where most of the discomfort or difficulty occurs. A total of 64 of 90 sewing machine operators completed this form. Neck, shoulder, and arm pain were commonly reported by these operators, with the symptom reports rarely dropping below 36% and ranging as high as 80%. The most numerous hand/wrist symptoms were numbness, cramping, and tingling sensations (varying from 43% to 60%). Despite the frequent occurrence among sewers of symptoms suggestive of upper limb musculoskeletal disorders, jobs rated high and low in ergonomic risk factors showed only small differences in the rate of the symptoms reported. Possible reasons for the lack of differentiation are given in the report [HETA 83–205–1702].