Blister (nonthermal), unspecified knee, initial encounter

This code signifies a non-burn related fluid-filled lesion on an unspecified knee. It indicates the initial presentation or treatment of such a blister, which could arise from friction, pressure, or other non-thermal causes.

Apply this code when documenting a patient's first encounter for a blister on the knee, where the cause is not a burn and the specific side (left or right) is not documented or is unknown. This is appropriate for conditions like friction blisters from clothing or footwear, or pressure blisters from prolonged kneeling.

• Ensure the documentation explicitly states "initial encounter" for this specific injury.
• If the laterality (left or right knee) is specified, a more precise code should be used.
• Confirm the blister is explicitly stated as "nonthermal" to avoid miscoding with burn injuries.