US Patent 9179984 Multi-configuration tracking array and related method

A navigation system generally determines a location of a portion of a first medical instrument relative to a patient. The navigation system generally includes a multi-configuration tracking array that extends from the first medical instrument. A plurality of tracking devices can be positioned on the multi-configuration tracking array. At least one of the tracking devices changes to define at least a first condition and a second condition. A tracking system detects the tracking devices and relates a change between the first condition and the second condition with a change between at least a first instrument configuration and a second instrument configuration.