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Physiatrist assessing a patient
|Synonyms||Physiatrist, rehabilitation medicine, physical and rehabilitation medicine (PRM)|
Physical medicine and rehabilitation, also known as physiatry, is a branch of medicine that aims to enhance and restore functional ability and quality of life to those with physical impairments or disabilities. A physician having completed training in this field may be referred to as a physiatrist. Physiatrists specialize in restoring optimal function to people with injuries to the muscles, bones, ligaments, or nervous system.
In the hospital setting, physiatrists commonly treat patients who have had an amputation, spinal cord injury, stroke, traumatic brain injury, and other debilitating injuries. In treating these patients, physiatrists lead an interdisciplinary team of physical, occupational, recreational and speech therapists, nurses, psychologists, and social workers. In outpatient settings, physiatrists also treat patients with muscle and joint injuries, pain syndromes, non-healing wounds, and other disabling conditions. Physiatrists are trained to perform intramuscular and interarticular injections as well as nerve conduction studies. 
During the first half of the 20th century, two unofficial specialties, physical medicine and rehabilitation medicine, developed separately, but in practice both treated similar patient populations consisting of those with disabling injuries. Frank H. Krusen was a pioneer of physical medicine, which emphasized the use of physical agents, such as hydrotherapy and hyperbaric oxygen, at Temple University and then at Mayo Clinic and it was he that coined the term 'physiatry' in 1938. Rehabilitation medicine gained prominence during both World Wars in the treatment of injured soldiers and laborers. Howard A. Rusk, an internal medicine physician from Missouri, became a pioneer of rehabilitation medicine after being appointed to rehabilitate airmen during World War II. In 1944, the Baruch Committee, commissioned by philanthropist Bernard Baruch, defined the specialty as a combination of the two fields and laid the framework for its acceptance as an official medical specialty. The committee also distributed funds to establish training and research programs across the nation. The specialty that came to be known as physical medicine and rehabilitation in the United States was officially established in 1947, when an independent Board of Physical Medicine was established under the authority of the American Board of Medical Specialties. In 1949, at the insistence of Dr. Rusk and others, the specialty incorporated rehabilitation medicine and changed its name to Physical Medicine and Rehabilitation.
The major concern that physical medicine and rehabilitation addresses is the ability of a person to function optimally within the limitations placed upon them by a disabling impairment or disease process for which there is no known cure. The emphasis is not on the full restoration to the premorbid level of function, but rather the optimization of the quality of life for those not able to achieve full restoration. A team approach to chronic conditions is emphasized to coordinate care of patients. Comprehensive Rehabilitation is provided by specialists in this field, who act as facilitators, team leaders, and medical experts for rehabilitation.
In rehabilitation, goal setting is often used by the clinical care team to provide the team and the person undergoing rehabilitation for an acquired disability a direction to work towards. Very low quality evidence indicates that goal setting may lead to a higher quality of life for the person with the disability, and it not clear if goal setting used in this context reduces or increases re-hospitalization or death.
Not only must a physiatrist know medical knowledge regarding a patient's condition, but they also need to know relevant/practical knowledge regarding it as well. This involves issues such as: what type of wheelchair best suits the patient, what type of prosthetic would fit best, does their current house layout accommodate their handicap well, and other every day complications that their patients might have. 
In the United States, residency training for physical medicine and rehabilitation is four years long, including an intern year. There are 83 programs in the United States accredited by the Accreditation Council for Graduate Medical Education, in 28 states.
Specifics of training differs from program to program but the base knowledge acquired is roughly the same. Residents are trained in the inpatient setting taking care of multiple types of rehabilitation including: spinal cord injury, traumatic brain injury, stroke, orthopedic, cancer, cerebral palsy, burn, pediatric rehab, and other disabling injuries. The residents are also trained in the outpatient setting to know how to take care of the chronic conditions patient's have following their inpatient stay. During training, residents are instructed on how to properly perform several diagnostic procedures which include electromyography and nerve conduction studies and also procedures such as joint injections and trigger point injections. 
Fellowship training for other unaccredited subspecialties within the field include the following: