A study was conducted for investigating the status of simple X-rays on lumbosacral regions at pre-employment health examination and analysing the effectiveness of simple X-rays on lumbosacral regions.

The study data were pre-employment health examination data in a university hospital from Jan 3, 1993 through October of 1997. And, 97 newly employed workers who claimed no low back pain at pre-employment health examination of a certain company were follow-up survey about low back pain and related factors in April, 1995 and October of 1997. The data were collected by a self-reported questionnaire and a medical examination with a rehabilitation specialist.

Taking the simple X-rays on lumbo-sacral regions was 1, 591 workers(10.5%) among 15,166 pre-employment health examination from Jan 3, 1993 through October of 1997. And yearly application rates of these X-ray tests have been significantly statistical increasing (p<0.01). 2. The abnormal findings of simple X-rays on lumbo-sacral regions at pre-employment health examination were 40 workers. But, there was not significantly statistical difference between normal and abnormal group for the complaint rate of low back pain. 3. The number of case with symptoms of low back pain at the follow-up survey were 46, so the incidence density was 37. 1 persons/ 100 person-years. And the incidence density was not significantly statistical difference between normal and abnormal group of simple X-rays on lumbo-sacral regions. 4. Through the multivariate logistic regression, significantly associated factors with low back pain were found to be tenure(OR=0.36, 95%CI: 0.17-0.79), lifting of heavy materials(OR=5. 86, 95%CI: l. 58-21. 74).

The simple X-rays on lumbo-sacral regions at pre-employment health examination is required further research for utilizing pre-employment health examination according to above results.