Fig. 2.

The varus-valgus low friction slide, which is shown disconnected from the support frame for clarity. The surgeon applies loads to the cart with the instrumented handle, causing it to translate on the rail. As the cart translates, the bearings on the fork interact with the peg of the boot that is resting on the fork, driving the leg into varus or valgus. Blocks at both ends of the cart have attachment points for the instrumented handle, allowing the stability test to be performed from both the medial and lateral sides of the patient. The fork is allowed to rotate with respect to the cart.