An internist is a physician who focuses on the diagnosis and treatment of conditions that affect the adult population—both acute and chronic.These doctors are often who adults see as their primary physicians because they treat a broad range of illnesses that do not require surgical or specialist interventions. They also work to help a patient maintain optimal health in order to prevent the onset of disease.In addition to treating the common cold and flu, internists also treat chronic diseases like diabetes and heart disease.

An orthopaedic surgeon is a physician who specializes in diagnosis and surgical treatment of injuries and disorders involving the musculoskeletal system, such as hip replacements and arthroscopic knee surgery.In addition to treating trauma to the musculoskeletal system, these doctors also deal with sports injuries, degenerative diseases, infections, tumors and congenital disorders.

A sports medicine specialist is a physician who is trained to diagnose and treat injuries and conditions caused by participation in athletic activities.These doctors are generally employed by professional sports teams to care for the athletes who are injured. They have extensive knowledge of the types of injuries that athletes are most susceptible to, such as stress fractures, sprains, concussions, muscle cramps, ACL injuries, and shin splints.It is the responsibility of sports medicine specialist to clear athletes to return to the playing field when they are deemed fit. These doctors also advise athletes on how to avoid injury through proper care of their bodies while training.

A surgical specialist is a physician who has additional training in a specific area of surgery.The American Board of Medical Specialties acknowledges the following surgical specialties: general surgery, thoracic and cardiac surgery, colon and rectal surgery, obstetrics and gynecological surgery, neurological surgery, ophthalmic surgery, oral and maxillofacial surgery, orthopedic surgery, otolaryngological surgery, pediatric surgery, plastic surgery, urological surgery, and vascular surgery.Some procedures are performed by more than one type of specialist. Also, some surgeons may choose to specialize in specific procedures within their specialty area. For example, a plastic and maxillofacial surgeon may specialize in performing rhinoplasty procedures.