[Roentgenological and histopathological studies of the hip joint in rheumatoid arthritis].

In order to study the disease process of the hip joint in rheumatoid arthritis, roentgenological analysis was carried out along with histological studies on the resected femoral heads. For the roentgenological study, hip roentgenograms of seven patients with known natural course and sixty preoperative patients were used. For the histological study, sixteen resected femoral heads affected by various disease types were used. The histological findings were compared with the roentgenological findings. As specific roentgenological findings, there were osteoporosis, burrowing and inward protrusion of the acetabulum, and collapse and flattening of the femoral head. A sequential process of the femoral head destruction was demonstrated, starting from collapse, through flattening, and finally ending in disappearance. The collapse was divided into sclerotic collapse and porotic collapse, and their roentgenological and histological differences were discussed. In addition to the common destruction process, the presence of the following three uncommon types was suggested for a better understanding of clinical manifestations: stiff type (4.5%), synovial proliferation type (6.0%) and aseptic necrosis type (3.0%).