Study on the Cervicobrachial Syndrome Among Microwave-oven Assemblers (III) : A Review on Working Posture / 대한산업의학회지

Working postures in 116 microwave-oven assemblers were measured and analysed using postural load scores of body parts in 137 workers complaining the cervicobrachial syndrome (CBS). The relationship between postural load scores of body parts and the grades of CBS was observed. Results were summarized as follows. 1. The height of work-table and work-seat, the thumb tip reach, the shoulder angle, the elbow angle and the forward bending angle of body trunk exceeded the recommended level and therefore they seemed to impose increased static postural loads on muscles of neck and shoulder as well as static and/or dynamic load on arm and hand muscles. 2. The postural load score of shoulder in grade II was significantly lower than that in grade III-2 and IV and those of elbow, neck+shoulder, elbow+wrist and upper extremity were significantly lower in grade II than in grade Iv. These results suggested that the awkward working postures were associated with the occurrence of CBS as well as the severity of CBS.

A Study on the Cervicobrachial Syndrome among the Microwave-oven Assemblers (I): A Review on the Symptoms Investigated by the Questionnaire / 대한산업의학회지

To find the characteristics of the subjective symptoms and its related factors among the patients with the cervicobrachial syndrome, an interview survey was made toward 137 patients complaining the symptoms in cervicobrachial area out of 313 workers occupied in a microwave-oven assembling factory from December 1993 to February 1994. Results were as follows : 1. The patients were classified by the severity of the syndrome as 6 persons (4.4%) at grade I (the mildest grade), 48 persons (35.0%) at grade II, 47 persons (34.4%) at grade III-1, 11 persons (8.0%) at grade III-2 and 25 persons (18.2%) at grade IV. 2. Only 3.6% of the total patients under the study felt the main symptoms of the cervicobrachial syndrome 36 months before this study, and then the number of patients increased gradually, but the incidence of the syndrome increased suddenly from 25.1% to 74.9% since the factory had elevated the height of the belt conveyer-worktables from 75.0cm to 87.7 cm 13 months before the study. 3. Although the higher percentage of the female workers felt the subjective symptoms including the pain at the neck and shoulder, the discomfort or pain at the back and the discomfort or pain at the wrist or the finger than male workers significantly (p<0.05). The male workers, however, showed more abnormal X-ray findings than the female workers significantly (p<0.05). 4. Between the prevalence of the cervicbbrachial syndrome and the number of actual workers occupied at the factory during last-24 months, a negative correlation (r=-0.508~r=-0.665) was observed. 5. The measured workplace environment of the studied factory (average temperature: 13.3 degrees C, average noise: 78.8 dB, average illumination: 241.4 Lux) was the poorer condition than the recommended level (17degrees C or more, lower than 75 dB and 400 Lux or more). 6. Neither items to check the cervicobrachial syndrome during the entrance and health maintenance examinations nor early treatment program for the syndrome were found, at the factory. In conclusion, the primary cause of the cervicobrachial syndrome of the workers were considered due to their repeated monotonous motions on the neck, the shoulder, the arms and the hands for a long duration (2-3 years) with the uncomfortable working posture under the uncomfortable workplace environments, and the condition got aggravated due to the inappropriated health management program for its secondary prevention.

A Study on the Cervicobrachial Syndrome among the Microwave-oven Assemblers (II): A Review on the Findings of the Examinations / 대한산업의학회지

To find the severity and the type of the cervicobrachial syndrome, through physical examinations and laboratory tests were made toward 137 patients complaining the cervicobrachial syndrome (CBS) through the health interview among 313 workers occupied in a microwave-oven assembling factory from December 1993 to February 1994. Results were as follows. 1. The prevalence of spontaneous pain was 94.9%, while 78.1% suffered from muscle tenderness, 63.5% suffered from muscle induration and 62.0% showed kinesalgia. 54.7% of patients showed positive cervical X-ray findings and 28.5% showed positive Morley test. 2. The muscle induration was associated with the total duration of the job among female workers. 3. The severity of neck tenderness was negatively correlated with the strength of the grip at both hands, positively correlated with the duration of overtime in male and the severity of the wrist tenderness was negatively correlated with the height in female. 4. X-ray findings, muscle induration, Morley test results, muscle tenderness on the neck and muscle tenderness on the shoulder were associated with subjective symptoms of the workers.5. The muscle tenderness was associated with the number of the complaints at upper extremities among the sufferings in daily life significantly and the electromyogram (EMG) finding was associated with; the number of the complaints: about neuropsychological system among the sufferings in daily life significantly. In conclusion, the results of the physical examination were related with the subjective symptoms of the cervicobrachial syndrome. The muscle induration, the muscle tenderness, cervical X-ray findings and the Morley test results were more useful for the diagnosis of CBS. More efforts to objectify the subjective symptoms were asked.