Abstract: A device immobilizes a shoulder joint and associated upper arm and forearm of a human patient in a selected relative position. The device comprises a platform including a planar base portion and a pair of opposed parallel side walls extending upwardly from the longitudinal edges of the base portion. The platform supportively receives and at least partially encloses the forearm of the patient. A mount defining a terminal slot is integral with at least one side wall. A belt is provided for securing around the waist of the patient. A belt clip attaches between the belt at a side of the body corresponding to the shoulder to be supported and the platform. The belt clip includes a lug projecting outwardly from the clip and corresponding in size and shape to the terminal slot for insertion into the slot, wherein the platform is suspended from the belt.