Prosthetic implant device
AssigneePrecision Cast Specialties, Inc.
InventorModest Khovaylo
Life of this patent
Estimating the term…
Abstract
A prosthetic joint for use in replacing the ball end of a biological joint, the replacement including a spherical head for insertion into a natural socket, an insert in the head and locked therein by an inwardly projecting ring in the head and a groove in the insert, a ball shaped member seated in the insert and having a neck and a stem for mounting the joint on the end of the biological member on which the ball is being replaced and a ring having a downwardly and inwardly sloping outer wall seating in a recess in the plastic insert and locking the ball shaped member in the insert.
Claims15
An implantable prosthetic joint for use in replacement of the ball end of a biological joint, said prosthetic joint having a metal spherical head for insertion into and seating in the natural socket of the joint, a bearing insert in said spherical head, said bearing insert having an outer spherical dome for engagement with the inner surface of said metal spherical head, an inner spherical dome and an outwardly extending recess at the entrance end of said inner spherical dome extending circumferentially around said entrance end and having an outwardly extending end wall and an outer wall extending downwardly from said end wall and sloping downwardly and inwardly toward said entrance, a ball shaped member seated in said inner spherical dome of said bearing insert and a ring intermediate said bearing insert and said ball shaped member, said ring having an end wall and an outer wall sloping downwardly and inwardly and in contact with said outer wall of said insert recess and an arcuate wall in contact with said ball shaped member, the length of said outer sloping wall of said ring being substantially shorter than the outer sloping wall of said recess in said bearing insert and permitting said ring to slide upwardly and expand in said recess in said bearing insert until said ball passes through said ring as said ball shaped member is inserted through the entrance end into said insert and to permit said ring to slide downwardly in said recess away from said recess end wall and wedge between said outer sloping wall of said recess and said ball shaped member when force is applied to said ball shaped member to withdraw said ball shaped member from said insert to lock said ball shaped member in said bearing insert and to permit said ring to be pushed by an unlocking tool upwardly in said recess in said bearing insert toward said outwardly extending end wall of said recess to permit said ring to be expanded outwardly sufficiently for said ball shaped member to be withdrawn through said ring and from said insert.
An implantable prosthetic joint for use in replacement of the ball end of a biological joint, said prosthetic joint having a spherical head for insertion into and seating in the natural socket of the prosthetic joint, a bearing insert in said spherical head having an inner spherical dome and an outwardly extending recess at the entrance end of said inner spherical dome extending circumferentially around said entrance end and having an outwardly extending end wall and an outer wall extending downwardly from said end wall and sloping downwardly and inwardly toward said entrance, a ball shaped member seated in said inner spherical dome of said bearing insert and a ring intermediate said bearing and said ball shaped member, said ring having an end wall and an outer wall sloping downwardly and inwardly and in contact with said outer wall of said insert recess and an arcuate wall in contact with said ball shaped member, the length of said outer sloping wall of said ring being substantially shorter than the outer sloping wall of said recess in said bearing insert and permitting said ring to slide upwardly and expand in said recess in said bearing insert until said ball passes through said ring as said ball shaped member is inserted through the entrance end into said insert and to permit said ring to slide downwardly in said recess away from said recess end wall and wedge betweenn said outer sloping wall of said recess and said ball shaped member when force is applied to said ball shaped member to withdraw said ball shaped member from said insert to lock said ball shaped member in said bearing insert and to permit said ring to be pushed by an unlocking tool upwardly in said recess in said bearing insert toward said outwardly extending end wall of said recess to permit said ring to be expanded outwardly sufficiently for said ball shaped member to be withdrawn through said ring and from said insert.
Dependencies are inferred from the claim text.