Hanger Prosthetics and Orthotics (a division of Hanger Orthopedic Group) (NYSE: HGR) provides prosthetic and orthotic patient care services in the United States. The company has more than 640 patient care centers located in 45 states and the District of Columbia. About 650,000 patients visit these centers each year. Hanger Prosthetics and Orthotics operates under the corporate umbrella of Hanger Orthopedic Group, Inc., headquartered in Austin, TX (formerly Bethesda, MD). According to the company's 2007 annual report, the patient care market for prosthetic and orthotic services in the United States is estimated at $2.5 billion annually. Hanger Prosthetics and Orthotics represents about 25 percent of this market. They employee about 3,500 people, including more than 1,080 prosthetic and orthotic practitioners.