A mechanical orthopaedic measuring/testing instrument used by a surgeon during the procedure to interrogate the strength and integrity of the ligaments that support (balance) the knee, prior to bony resection for a total knee arthroplasty (TKA). This may provide information essential to the selection of an optimal type of knee prosthesis. It is typically a spring-loaded device with dual-force scales that uses integral paddles to push against the rejected tibia and unresected femoral condyles. The surgeon can increase the force applied and obtain readings from the scales. This is a reusable device.