Blister (nonthermal), right knee, initial encounter

This code signifies the presence of a fluid-filled lesion on the right knee, not caused by heat or cold exposure. These blisters typically result from friction, pressure, or contact with irritants, leading to separation of skin layers and fluid accumulation.

This code is appropriate for documenting a patient's initial presentation for a non-thermal blister located specifically on the right knee. It should be used when the blister is the primary reason for the encounter or a significant co-morbidity being addressed.

• Ensure the blister is explicitly documented as non-thermal and located on the right knee.
• Verify this is the patient's first encounter for this specific injury; subsequent encounters will require a different seventh character.
• Consider additional codes for underlying causes if known (e.g., contact dermatitis, friction).