Abstract: A therapeutic apparatus for the prevention of ischemic ulcers and treatment for the soreness and stiffness of joints of patients suffering from arthritis, Parkinson's disease and the like. In the apparatus a patient rests on a surface such as that provided by a conventional mattress and bed which surface is oscillated through an included angle in the range of about 2 to 6 degrees in a generally vertical plane extending generally parallel to the longitude of the patient at a rate of about 15 to 150 seconds per each sweep through the included angle.