Patent ID: 8092545

Claim:
A method of performing knee arthroplasty comprising the steps of: (a) providing a multi-piece tibial component, the tibial component including (i) a tibial base having an inferior surface for engagement with a prepared surface at the proximal end of a tibia and a passageway extending through the base, the passageway including an open proximal end, an open distal end, and a portion which tapers inwardly in a distal direction, the tibial base further including an enlarged threaded aperture adjacent said superior surface and defining a shoulder extending outwardly from the portion which tapers inwardly, and (ii) a tibial stem including a tapered extension shaped to snugly engage the tapered portion of the passageway and a threaded flange portion shaped to threadably engage the enlarged threaded aperture of the tibial base, the threaded flange positioned proximal of the tapered extension; (b) preparing the proximal end of a tibia including forming a cavity along the intramedullary canal of the tibia; (c) positioning the tibial base on the prepared tibia proximal end; (d) thereafter positioning the tibial stem through the passageway in the tibial base, wherein a portion of the tibial stem is retained within the passageway and a portion of the tibial stem extends distally from the open distal end of the passageway and into the prepared cavity; and (e) securing the tibial base and the tibial stem together by threadably engaging the threaded flange portion of the tibial stem with the threaded aperture of the tibial base, such that the tapered extension of the tibial stem is lockingly engaged with the passageway of the tibial base, said step of securing the tibial base including leaving a gap between a distal side of the threaded flange and a proximal surface of the shoulder to ensure that the threadably engaging step effects locking engagement of the tapered extension and tibial base.