A PROSTHESIS DEVICE FOR THE HUMAN ANKLE ARTICULATION

摘要

A prosthesis device ( 1 ) for correct replacing of the articular surfaces of the human ankle joint comprises: a first component ( 2 ) having a spherical convex articular bearing surface ( 5 ); a second component ( 3 ) having a bearing surface ( 6 ) which has a convex shape in the frontal plane, and concave sulcus in the frontal plane; and a third component ( 4 ) located between said first and second components ( 2, 3 ) and having two surfaces ( 7, 8 ) which are complementary to and engage the upper convex and the lower concave sulcus surfaces ( 5, 6 ) to be fully congruent with the components ( 2, 3 ). The three components ( 2, 3, 4 ) can be designed from the subject-specific geometry of the ligaments ( 9, 10 ). The device ( 1 ) can move under natural muscular and ligamentous control, closely restoring that of a natural joint and maintaining uniform load distribution. A prosthesis device ( 1 ) implanted according to a stated method of ensuring equal dorsi- and plantar-flexion gaps between first ( 2 ) and second ( 3 ) components, is a part of the invention.