arm cylinder cast, an orthopedic device of plaster of paris, fiberglass, or thermoplastics used for immobilizing the upper limb from the wrist to the upper arm. It is most often applied to aid the healing of a dislocated elbow, for postoperative immobilization or positioning of the elbow, or in the correction of an elbow deformity, and treatment of forearm and humerus fractures.
