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.
Last update: 2006 Federal election (May 2013). The Politics of Mexico take place in a framework of a federal presidential representative democratic republic whose government is based on a congressional system, whereby the president of Mexico is both head of state and head of government, and of a multi-party system.he constituent states of the federation must also have a republican form of government based on a congressional system as established by their respective constitutions.