An orthotic device for restoring range of motion to a patient's limb, includes a first device cuff configured for attaching the device to an upper region of a patient's limb above a limb joint, a second device cuff configured for attaching the device to a lower region of the patient's limb below the limb joint, and a spring attached between the first and second cuffs for bending in a manner counteracting muscle contraction of the limb to which the device is attached, the spring having spring characteristics whereby a counteracting spring force of the spring increases during an initial flexing of the spring through a first angle range, then remains peaked during a subsequent flexing of the spring through a second angle range and finally decreases with a subsequent flexing of the spring through a third angle range.