| 摘要 |
1485295 Hip joint prosthesis MINNESOTA MINING & MFG CO 26 Nov 1974 51215/74 Heading A5R A implantable prosthetic joint comprises a head 22 for insertion into the socket member of the biological joint, a bearing insert 24 for insertion in said head, the insert having a spherical seat 44, a ball shaped member 70 for seating in said spherical seat 44 and means 72 for attaching said ball shaped member to the second anatomical member of the joint being partially replaced; the bearing insert includes attaching means 60 for retaining it in said head and is of one piece having a plurality of arcuate sections at its open edge, which when said head is removed are flexible outwardly to allow said ball shaped member to be inserted into said bearing insert and which, when said ball shaped member is in the spherical seat and the head is placed over the bearing insert, are engaged by said head for retaining said ball shaped member in the bearing insert. The bearing insert may be formed of ultra-high molecular weight polyethylene and all the other parts of cobalt chrome molybdenum alloy or of stainless steel. As shown the means 72 for attaching the ball shaped member to the second anatomical member of the joint is an intramedullary shaft. The diameter of the ball shaped member is not more than 65% of the diameter of the head resulting in a difference in torque which means that the head normally remains stationary in the socket member of the biological joint. As described, the joint is a hip prosthesis but it is stated that the joint may be used in a shoulder. |
