Orthopedia is the surgical specialism that treats bone pathologies and conditions affecting the musculoskeletal system. This field treats not only fractures, but also conditions of the tendons, muscles, and joints. Orthopedic surgeons can therefore treat bone malformations in order to allow a previously unusable system to function. They can replace senescent or arthritic joints with prostheses, heal bone or joint infections, or remove hematomas in the fascial compartments of the muscle. Immobilization of a fracture bone with a plaster cast is a common procedure when surgery in unnecessary, and also constitutes part of an orthopediatrist's role.