Patella trial implant

A patella trial implant comprising:

• a fixation member having a longitudinal axis extending between a posterior portion and an anterior portion, the anterior portion being configured for fixation to a resected patella;
• and
• a patella component having a posterior articular surface configured to articulate with a femoral surface and having an anterior contact surface configured to contact the resected patella and defining a frontal plane of the patella component,
• the patella component comprising a guide slot defining at least one guide axis extending longitudinally in parallel to the frontal plane, wherein the posterior portion of the fixation member engages in the guide slot, and wherein the patella component and the fixation member are movable relative to each other in translation along the at least one guide axis and in rotation about the longitudinal axis of the fixation member,
• wherein the guide slot has a plurality of slot sections being interconnected at a juncture and extending longitudinally along different guide axes, along which different guide axes the fixation member and the patella component are movable relative to one another.

A patella trial implant comprising:

• a fixation member having a longitudinal axis extending between a posterior portion and an anterior portion, the anterior portion being configured for fixation to a resected patella;
• and
• a patella component having a posterior articular surface configured to articulate with a femoral surface and having an anterior contact surface configured to contact the resected patella and defining a frontal plane of the patella component,
• the patella component comprising a guide slot defining at least one guide axis extending longitudinally in parallel to the frontal plane, wherein the posterior portion of the fixation member engages in the guide slot, and wherein the patella component and the fixation member are movable relative to each other in translation along the at least one guide axis and in rotation about the longitudinal axis of the fixation member,
• wherein the patella component has a locking mechanism which is operatively connected to the posterior portion of the fixation member and/or the guide slot and by means of which locking mechanism relative mobility between the fixation member and the patella component can be locked.

A patella trial implant comprising:

• a fixation member having a longitudinal axis extending between a posterior portion and an anterior portion, the anterior portion being configured for fixation to a resected patella;
• and
• a patella component having a posterior articular surface configured to articulate with a femoral surface and having an anterior contact surface configured to contact the resected patella and defining a frontal plane of the patella component,
• the patella component comprising a guide slot defining at least one guide axis extending longitudinally in parallel to the frontal plane, wherein the posterior portion of the fixation member engages in the guide slot, and wherein the patella component and the fixation member are movable relative to each other in translation along the at least one guide axis and in rotation about the longitudinal axis of the fixation member,
• wherein the patella component has a base plate and a top member mounted onto the base plate, wherein the base plate comprises the anterior contact surface and the guide slot, and wherein the top member comprises the posterior articular surface.