Abstract: An orthopedic prosthesis including a trunk engaging means, an arm engaging means and a lift assist means. The trunk engaging means includes a shoulder engaging means comprised of a strap which passes over the injured shoulder and a support plate attached to each end of the shoulder strap, the support plates being positioned in front of and behind the shoulder to be supported. The trunk engaging means also includes a lateral support strap, one end of the strap being connected to one of the support plates and around the body of the wearer under the arm opposite of the shoulder to be supported where it is connected to the second support plate. The arm engaging means includes a strap passing around the humerus of the arm of the wearer. The lift assist means utilizes two pulley systems, one mounted on the arm engaging means and one on the support plate of the shoulder engaging means.