Stress fracture, left ankle, subs for fx w nonunion

This code signifies a stress fracture affecting the left ankle that has failed to heal properly, resulting in a nonunion. It indicates that the patient is receiving active treatment for this nonunion, such as surgical intervention or cast changes, following the initial fracture management.

Apply this code when documentation clearly states a stress fracture of the left ankle with nonunion, and the patient is currently undergoing treatment for this nonunion. This includes follow-up visits for ongoing management, surgical procedures to address the nonunion, or evaluation of treatment effectiveness. Documentation should specify "nonunion" and the "left ankle" as the affected site.

• Ensure documentation explicitly states "nonunion" and not just delayed healing.
• This code requires an additional code for any associated external cause or activity if applicable.
• Distinguish from initial encounter (A), subsequent encounter for routine healing (D), or sequela (S) codes.