Abstract: An extremity support device which may be for a leg or arm to relieve strenuous physical handling of an extremity of a patient by medical personnel when treating the extremity of a patient, for example, as during the application of a cast thereto. The device is arranged to support a leg or arm at a select elevation and assist a physician in the application of a cast thereto, making it possible for one person to perform this operation. The device has an L-shaped support pad made from a foam material having a recess at the juncture of the legs of the L, for receiving the heel or elbow of the patient in elevated relation with respect to a bed or table upon which the patient may be lying or sitting. The bottom and side of the device opposite the recess may be provided with a non-skid material, enabling the device to be positioned on the bottom or end thereof so as to provide a non-moving, safe support while treatment is underway.