I understand what internal fixation is, but my books says that external fixation is a method that is used when internal fixation is not feasible and it is called external fixation with closed reduction.
A committee is a body of one or more persons that is subordinate to a deliberative assembly. Usually, the assembly sends matters into a committee as a way to explore them more fully than would be possible if the assembly itself were considering them. Committees may have different functions and their type of work differ depending on the type of the organization and its needs.
A committee created in the rules of either house that meets throughout the two years of a congressional session (e.g., the 109th Congress) to consider and report on measures referred or tasks assigned to it by the respective presiding officers.