Microwave diathermy uses electromagnetic radiation through microwaves to heat tissue more superficially than short-wave diathermy. It is primarily used to heat superficial muscles and joints like the shoulder. Microwave diathermy utilizes electromagnetic radio waves with frequencies of 915 and 2456 MHz. Therapeutic benefits include making collagen tissue more flexible, reducing muscle spasms, and treating joints in the hands, feet, and wrists as well as strains and sprains.