T23.729A Corrosion of third degree of unspecified single finger (nail) except thumb, initial encounter

Billable ICD-10-CM code, FY2026.

Built from T23.729 with 7th character A (initial encounter).

Applies from T23 Burn and corrosion of wrist and hand

7th character note

• The appropriate 7th character is to be added to each code from category T23

7th character required

• A — initial encounter
• D — subsequent encounter
• S — sequela

Applies from T23.7 Corrosion of third degree of wrist and hand

Code first

• (T51-T65) to identify chemical and intent

Use additional code

• external cause code to identify place (Y92)

Medicare Code Edits (MCE v43.1 (April 2026))

• Unspecified code (laterality): Unspecified codes for which a more specific code identifying laterality (right, left, bilateral) exists within the same code family.

Code annotations containing back-references to T23.729A

Back-references to T23

• Type 2 Excludes: T22 Burn and corrosion of shoulder and upper limb, except wrist and hand ("burn and corrosion of wrist and hand (T23.-)")
• Type 1 Excludes: T66 Radiation sickness, unspecified ("burns (T20-T31)")
• Type 2 Excludes: T67 Effects of heat and light ("burns (T20-T31)")
• Type 2 Excludes: T75 Other and unspecified effects of other external causes ("burns (electric) (T20-T31)")

Diagnosis Index entries for T23.729A

• Corrosion (injury) (acid) (caustic) (chemical) (lime) (external) (internal) › finger › third degree

Nearby codes

• T23.722 Corrosion of third degree of single left finger (nail) except thumb
• T23.722A Corrosion of third degree of single left finger (nail) except thumb, initial encounter
• T23.722D Corrosion of third degree of single left finger (nail) except thumb, subsequent encounter
• T23.722S Corrosion of third degree of single left finger (nail) except thumb, sequela
• T23.729 Corrosion of third degree of unspecified single finger (nail) except thumb
• T23.729A Corrosion of third degree of unspecified single finger (nail) except thumb, initial encounter (this code)
• T23.729D Corrosion of third degree of unspecified single finger (nail) except thumb, subsequent encounter
• T23.729S Corrosion of third degree of unspecified single finger (nail) except thumb, sequela
• T23.73 Corrosion of third degree of multiple fingers (nail), not including thumb
• T23.731 Corrosion of third degree of multiple right fingers (nail), not including thumb
• T23.731A Corrosion of third degree of multiple right fingers (nail), not including thumb, initial encounter