Blister (nonthermal), left knee, sequela

This code signifies a non-heat-related blister located on the left knee, representing a residual condition or late effect of an earlier injury or disease. It indicates that the blister is no longer an acute event but rather a persistent or recurring issue stemming from a previous cause.

Use this code when documenting a patient presenting with a blister on their left knee that is a long-term consequence of a prior injury, friction, or other non-thermal etiology. This is appropriate for follow-up visits where the original cause has resolved, but the blister remains a chronic or recurrent problem.

• Ensure documentation clearly links the blister to a previous, resolved condition or injury.
• Do not use for acute, currently forming, or actively healing blisters from a recent event.
• Always sequence this code after the code for the original condition or external cause, if applicable and still relevant.