Patent ID: 8435304

Claim:
An adjustable tibial trial insert, comprising: an upper plate including an upper articular surface, the upper articular surface including a concave surface, a lower plate including a lower surface configured to engage a top surface of a tibial tray, and a height-adjustment mechanism coupled to and positioned generally between the upper plate and the lower plate and configured to move between a closed position where the upper and lower plates are adjacent each other and an opened position where the upper and lower plates are spaced-apart from each other, wherein the height-adjustment mechanism includes: a drive coupled to the upper plate and the lower plate, the drive including (i) a first crossbar having a first end pivotally coupled to the upper plate and a second end pivotally and slidably coupled to the lower plate, and (ii) a second crossbar having a first end pivotally and slidably coupled to the upper plate and a second end pivotally coupled to the lower plate, and an actuator coupled to the drive and to one of the upper and lower plates, wherein the actuator includes a knob and a link pivotably coupled to the drive and coupled to the knob for rotation with the knob.