摘要 |
<p>The prosthesis i.e. lumbar prosthesis, has two shells (5, 6) extending mainly in a plane, and a flexible element i.e. spherical ball (7), that is interposed between the two shells. The flexible element is arranged with two contact zones on two opposed sides of the shells. Each of the shells is arranged with a face having a round form. The faces are formed by cups arranged as hollow spheres in the center of the shells. The shells form a free space (28) surrounding a periphery unit of the flexible element arranged outside of the contact zones.</p> |