If a patient has lost the distal one-third of a lower extremity, what is the injury called?

When a patient loses a portion of a limb, specifically the distal one-third of the lower extremity, the injury is classified as an amputation. An amputation refers to the surgical or traumatic removal of a limb or extremity. In this case, it indicates that the lower extremity has been severed or removed at a point near the foot, which constitutes a significant loss of anatomical structure and function.

Understanding the context of other options can help clarify why amputation is the correct choice. For instance, an avulsion typically refers to an injury where a body structure is forcibly detached from its normal point of insertion, such as skin or flesh being torn away, but does not necessarily imply complete loss of the extremity. Furthermore, terms like "amplitude" and "extremity exodus" are not commonly used in the context of injuries related to limb loss or trauma. Therefore, identifying the correct term for the complete loss of a section of a limb relies heavily on the precise definition of amputation, making it the most appropriate answer in this scenario.