| 摘要 |
The anchor (10) has circular main structure (2) comprising proximal tip end which is tapered towards a distal end. A tab (3) is constructed within the largest diameter of main structure to form a centrally provided irregular octagon whose outline consists of two broad surfaces, two longitudinal surfaces and four guiding surfaces. The longitudinal surfaces have length of broad surfaces, and the broad-surfaces have the length of guiding surfaces. The tab has longitudinal surfaces arranged at right angles, while a penetrating opening (8) is formed in width of the tab. |
