Unsp opn wnd unsp front wall of thrx w penet thor cav, sqla

This code describes a long-term complication or late effect resulting from an unspecified open wound to the front of the chest, where the wound extended into the thoracic cavity. The specific location on the front wall of the thorax is not documented, and the nature of the open wound is also unspecified.

This code is appropriate for documenting sequelae of a penetrating chest injury to the anterior thorax when the original injury occurred in the past and the specific details of the wound and its exact location are no longer available or were never precisely documented. It is used when the patient is presenting for treatment of a residual condition directly attributable to that prior injury.

• Always assign an external cause code (V00-Y99) to describe the circumstances of the original injury, if known.
• Ensure documentation clearly indicates the condition being treated is a sequela (late effect) of the original injury.
• Avoid this code if more specific information regarding the wound type, location, or laterality is available; instead, use a more precise S21.3- code with the appropriate 7th character.