A hinge assembly is provided for an orthopedic knee brace. The knee brace includes upper and lower support arms. The hinge assembly includes a hinge plate and first and second gear members pivotally connected to the hinge plate. The first gear member is coupled for rotation with the upper support arm and has an articulation surface adjacent a surface of the upper support arm. The second gear member is coupled for rotation with the lower support arm and has an articulation surface adjacent a surface of the lower support arm. The hinge assembly allows medial/lateral articulation of the upper and lower support arms in a plane substantially perpendicular to a plane of rotation of the first and second gear members.