Corrosion of unsp degree of left thumb (nail), sequela

This code describes the long-term effects or complications resulting from a chemical burn of an unknown severity affecting the left thumb, specifically including the nail. These sequelae could include scarring, nail deformities, chronic pain, or functional impairment that persists after the initial injury has healed.

Use this code when documenting a patient presenting with a current condition or symptom that is a direct consequence of a past corrosion injury to their left thumb. This is appropriate for follow-up visits addressing chronic issues stemming from the original chemical burn, rather than the acute injury itself.

• Always sequence this code after the code(s) for the specific sequela being treated (e.g., scar, deformity).
• Ensure documentation clearly links the current condition to a past corrosion of the left thumb.
• Avoid using this code for acute or active corrosion injuries; use the appropriate acute T23.x12A or T23.x12D codes instead.