Milwaukee sewerage tunnel project.
Dysbarism-related osteonecrosis: proceedings of a symposium on dysbaric osteonecrosis. Beckman EL, Elliott DH, eds. Cincinnati, OH: U.S. Department of Health, Education, and Welfare, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 75-153, 1974 Jan; :41-46
The incidence of bone disease among men working in tunnel construction prior to the adoption of a more rigid code of decompression procedures in 1970 was reviewed. A group of 188 men working in sewer tunnel construction in Milwaukee were examined, 169 of whom had previous exposure to compressed air at pressure greater than 16 pounds per square inch gage (psig). Of the men with previous exposure at pressures greater that 16psig, 59 (35 percent) had lesions of aseptic necrosis. Forty two of the men with the disease (71 percent) had potentially disabling juxta articular lesions; 16 of these were already symptomatic. In the whole group, 26 additional men had classic bone islands. Of these 26, only three had never worked in compressed air. Work under the old regulations was done with split shift tables using modifications of the 1922 New York code, which provided inadequate decompression time. In 1971, decompression tables were designated as the national standard for all compressed air work done in the U.S. Since that time there has been no occurrence of a well documented case of aseptic necrosis. To adequately x-ray a caisson worker, the series should include two views of the shoulders, two views of the hips, and A-P and lateral views of each knee for a total of 12 films. Both gonadal and pelvic shielding were required. Some diagnostic films were presented and discussed.
Bone-structure; Bone-disorders; Tunneling; Tunnel-workers; Construction-workers; Decompression-sickness; Osteogenesis; Caisson-disease
Dysbarism-related osteonecrosis: proceedings of a symposium on dysbaric osteonecrosis