The orthesis has band sections (10, 12) attached to the orthesis at a region of an upper leg and a lower leg, and a flexible band (19) connected with a base part and laterally extended. Elastic forces of the band sections and the flexible band are selected in such a manner that the band is extended from an extended position during deflection of a knee joint. An expansion limiter (23) is provided for the flexible band and is effective with a predetermined deflection limiting angle of the knee joint, so that the band sections are predominantly expanded for large deflection of the joint.
