Abstract: The present invention relates generally to a therapeutic device and related methods for treating arthritis of the knee. The therapeutic device includes a stretchable band having a predetermined length, a flexible and resilient body installed in the longitudinal middle of the stretchable band with a substantially triangular cross-section whose height is greater at one side of the stretchable band than at the other, such that the higher portion of the flexible and resilient body is applied to the sole at a position nearer to the inner or outer side thereof, and the stretchable band may be used to wrap and fix the ankle.