This device is a particular case used in the Bier thermotherapy, a branch of physiatrics that uses heat as a therapeutic tool for the treatment of osteo-articular pathologies. The case is composed of a wooden box with an arched shape, inside which is placed the heat source, generated by electric bulbs. The disease part of the body was placed inside the case for the treatment. The Bier case was used in the aftermath of fractures, in traumas during sports exercises (contusions, muscle tears), in rheumatic and uricemic forms, in neuralgia, etc..