Endoprosthetic bone joint devices
AssigneeNational Research Development Corporation
InventorsDavid M. Evans, Barry O. Weightman
Life of this patent
Estimating the term…
Loading patent…
AssigneeNational Research Development Corporation
InventorsDavid M. Evans, Barry O. Weightman
Estimating the term…
Endoprosthetic metacarpal phalangeal joint devices are well known in various forms including unitary flexible structures for connection between the bones, and others with separate phalangeal and metacarpal components for respective bone connection and inter-engagement or connection for mutual articulation in a hinge action. All such devices are applied individually to respective joints and can tend to fail due to conditions leading to ulnar drift. It is now proposed that this tendency be obviated by mechanically interconnecting a plurality of devices of the latter form in the hand, suitably by use of a common hinge pin. The pin preferably has slight longitudinal curvature to pass through the natural joint centers. The phalangeal components preferably each have a socket for bone connection and a stem for axle connection, the stem being slidably and rotatably received in the socket to accomodate torsional loading.
An endoprosthetic MCP joint assembly (10) comprising a plurality of devices (11) which each include a pair of phalangeal and metacarpal components (12, 13) for respective connection to the bones of an individual MCP joint, and wherein each of said devices include a common pin member (14) hingedly connecting the components of each of said devices.
An assembly according to any of the preceding claims wherein said pin member has a respective radially enlarged stop (27) at each end thereof, at least one such stop being separably connected to the pin member.
A method for surgical treatment which comprises connecting a pulurality of endoprosthetic hinge devices each including a pair of phalangeal and metacarpal components for respective connection to the bones of an individual MCP joint and mechanically interconnecting each of said devices with a common pin member through a hinge portion of said components to stabilize the same against ulnar drift.
Dependencies are inferred from the claim text.