Total knee replacement may be done on people, usually over 55, whose knees have been damaged by arthritis, trauma, or other destructive diseases of the joint resulting in severe limiting knee pain and significant stiffness, instability (constant giving way) and deformity (lock-knees or bowlegs) of the knee.
The Mexican government has a Federal District, which houses the federal government. The Federal District is a physical place and a territory, bordering Mexico City, which is the country's capital city. This is not counted as one of the states, and is much like the United States' District of Columbia.
Mexico has a population of 112,468,855 (July 2010 estimate) and its capital and largest city is Mexico City. Mexico is divided into 32 federal entities, of which 31 are states and one is a federal district. The following is a list of Mexico's 31 states and one federal district arranged by area. The population (as of 2009) and capital of each have also been included for reference.