| 摘要 |
The stem of the cephalic femoral component of a hip prosthesis is bounded by two pairs of longitudinally extending surfaces including two relatively wide and two relatively narrow surfaces. At least one of the narrow surfaces is convex, all of the surfaces taper in a direction toward a rounded tip of the stem, the radius of curvature of the convex surface or surfaces decreases in a direction toward the tip, and the wider surfaces taper toward each other in a direction from the one toward the other narrower surface. This reduces the likelihood of loosening of the stem in the medullar canal of the femur wherein the stem is implanted without cement, and the bone around the stem is less likely to be subjected to excessive localized stresses. |
