US Patent 7632314 Adjustable knee tibial trial insert

An adjustable tibial trial insert includes an upper plate having an upper articular surface and a lower plate. A height-adjustment mechanism of the insert is coupled to and positioned generally between the upper plate and the lower plate and is 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 in order to adjust a height or thickness of the insert.