Orthopaedic surgical instrument system having an anterior-loading tibial bearing trial and associated surgical method of using the same

An orthopaedic surgical instrument, comprising:

• a tibial bearing trial, comprising:
• an inferior surface,
• a superior surface opposite the inferior surface and having a pair of curved bearing surfaces formed therein,
• a spine positioned between the pair of curved bearing surfaces,
• a sidewall extending between the inferior surface and the superior surface, and
• a channel formed in the inferior surface, wherein (i) a posterior end of the channel is defined by an opening formed in a posterior section of the sidewall, (ii) an anterior end of the channel is defined by a rounded sidewall so as to define a round cavity, (iii) medial and lateral sides of the channel are defined by a pair of deflectable flanges, (iv) each of the pair of deflectable flanges has a cam lobe formed therein, and (v) the cam lobes extend inwardly into the channel toward one another.

A method of trialing an orthopaedic prosthetic assembly, the method comprising:

• aligning a tibial bearing trial with a tibial base trial positioned on a proximal end of a patient's tibia,
• advancing the tibial bearing trial in the anterior-to-posterior direction to move a post of the tibial base trial component into a posterior channel defined in the tibial bearing trial,
• capturing the post of the tibial base trial in the channel between a pair of deflectable flanges so as to snap-lock the tibial bearing trial to the tibial base trial such that the tibial bearing trial is permitted to rotate relative to the tibial base trial, and
• moving the patient's joint through a range of motion including extension and flexion to evaluate a configuration of the orthopaedic prosthetic assembly corresponding to the tibial base trial and the tibial bearing trial.