手根溝の構築についての研究
1982 年 94 巻 1-2 号 p. 73-86
詳細
1982 年 94 巻 1-2 号 p. 73-86
In order to study the transverse osseous architecture of the carpal region, eight wristhand specimens were obtained from four cadavers. The specimens were embedded in polyester resin after the soft tissues had been removed completely. The embedded specimens were cut into serial sections. The cutting was carried out perpendicular to the longitudinal axis of the third metacarpal bone. Each section was examined by microradiography. The shape of the bones, the width and the area of the carpal sulcus as well as the trabecular architecture were studied. The results were summarized as follows:
1. The bone shapes were divided into six groups, i.e. radio-ulnar joint level, proximal level of carpals, intermediate level of carpals, distal level of carpals, the first CM joint level and the metacarpal base level. The carpal sulcus corresponded to the intermediate, distal carpal level and to the first CM joint level.
2. Prominence of a volar arch of the carpal sulcus was observed not at the center of the arch but at the ulnar side. This prominence shifted more to the ulnar side in the distal level of carpals than in the proximal level. From these findings it was considered that the prominence of the volar arch functioned as a pulley for the flexor tendons of fingers in grasping.
3. Although the width of the carpal sulcus became narrower towards the distal level of the carpals, the largest area was obserbed at the distal level. From these observations, the cause of the carpal tunnel syndrome was considered to be an imbalance between the volume of the carpal tunnel and its contents such as flexor tendons and nerves.
4. The articulations of carpal bones indicated that the motion center of the carpal bones was situated at the head of the capitate.
5. The trabecular orientation was divided into three groups: trabeculae perpendicular to the joint surface, trabeculae crossing each other at right angles which were observed at radial and ulnar prominences of the carpal sulcus, and trabeculae arranged without interruption through the arch of the carpal sulcus.
