This is the rotational expression of varus force.
As with valgus torque, varus torque increases as varus force increases and as the force's distance from the axis of rotation increases.
Passive varus torque is supplied primarily by the ulnar collateral ligament (UCL). The UCL does not contract, so its contribution to varus torque is a passive tension caused by valgus torque.
Active varus torque is supplied by the flexor-pronator mass.
A small amount of inertial varus torque is present during the deceleration phase of the delivery.