平成16年度前期国際研究集会派遣会員報告書(学術交流委員会だより)

Abstract

The most common type of scaphoid bone fracture is the transverse fracture of the waist (central 1/3). However, traditional Positioning frequently fail to visualize fracture line. This may be caused by the fact that X-rays cannot be irradiated perpendicularly onto the scaphoid long axis. In this study we searched with the optimal limb position for visualizing the waist of the scaphoid bone. In 30 volunteers, the scaphoid bone was taken in the ulnoradial direction at 40 degrees ulnar deviation (group A) and 40 degrees ulnar deviation with the fist clenched (group B) , and measured the angle between the cassette plane and the long axis of the scaphoid (C-S) and also the angle between the cassette plane and the volar tilt (C-V) . The C-S angle at group A was 32.5+/-9.9 degrees and at group B was 15.8+/-7.5 degrees . The C-V angle was 12.1+/-3.2 degrees . It was suggested to should be lifting upward the distal suprapalmar side at about 30 degrees in group A, at about 15 degrees in group B. These positioning make the long axis parallel to the cassette. Especially, the later view was able to visualize the ulna-scaphoid joint more clearly without overlap of radius and scaphoid bones as compared to with traditional methods. In fractures of the scaphoid bone, in which early diagnosis is critical, optimization of first-choice X-ray imaging is a key factor, and an additional image involving a 15 degrees scaphoid waist view will be useful.