Modular patella trials

A modular patella trial system comprising:

• an articulating surface element having a length, a width, and a thickness, the articulating surface element having a posterior surface and an anterior surface separated by the thickness of the articulating surface element and further having an outer surface, the outer surface having at least one tongue extending outwardly therefrom;
• and
• at least one mating element having a length, width, and thickness, the at least one mating element having a posterior surface and an anterior surface separated by the thickness of the mating element and further having an exterior surface, the exterior surface further having at least one groove extending inwardly therefrom;
• and
• wherein the at least one groove of the at least one mating element is adapted to receive the at least one tongue of the articulating surface element such that the modular patella trial system has a thickness substantially equal to the total of the thicknesses of the articulating surface element and the at least one mating element.

A modular patella trial system comprising:

• an articular button having a length, a width, and a thickness, the articular button including a posterior surface and an anterior surface separated by the thickness of the articular button, the anterior surface having at least one protrusion extending outwardly therefrom;
• and
• a bone protector plate capable of placement onto a resected surface of a patella having a length, width, and thickness, the bone protector plate including a posterior surface and an anterior surface separated by the thickness of the bone protector plate, at least one fixation cavity extending into the posterior surface thereof, and at least one peg extending from the anterior surface thereof,
• wherein the at least one fixation cavity is capable of receiving the at least one protrusion of the articular button, and
• wherein the at least one peg is capable of insertion into at least one cavity on the resected surface.

A method for reconstructing a patella of a patient, the method comprising the steps of:

• determining a portion of the structure of a patella to be removed;
• removing the predetermined portion of the patella to form a resected surface;
• determining the thickness of the resected patella;
• placing a peg preparation instrument having an anterior surface and a posterior surface separated by a thickness, said peg preparation instrument further having at least one opening through said thickness, wherein the at least one opening is capable of receiving a boring instrument through the entire thickness, against the resected surface of the patella;
• boring at least one hole into the resected surface of the patient's patella;
• determining a surface profile of the patella;
• removing the peg preparation instrument from contact with the resected surface of the patella;
• placing a preselected bone protector plate on the resected surface of the patella, wherein the bone protector plate has at least one protrusion extending from the bone protector plate and at least one fixation cavity, such that the protrusion is removably inserted into the at least one hole of the resected surface of the patella, and wherein the bone protector plate has a profile substantially corresponding to the profile of the resected patella;
• placing a preselected articular button on the bone protector plate, wherein the articular button has a posterior surface having a profile and an anterior surface having at least one peg, the posterior and anterior surfaces separated by the thickness of the articular button, such that at least one peg of the articular button is removably inserted into the cavity of the bone protector plate to form a trial assembly of the articular button, bone protector plate, and patella;
• removing the bone protector plate from contact with the resected surface of the patella;
• determining a proper permanent implant for insertion into the at least one hole on the resected surface of the patella;
• and
• inserting the permanent implant into the at least one hole on the resected surface of the patella.