T23.012A Burn of unspecified degree of left thumb (nail), initial encounter

ICD-10-CM T23.012A: Burn of unspecified degree of left thumb (nail), initial encounter

ICD-10-CM code T23.012A identifies a burn of unspecified degree of the left thumb (nail) for an initial encounter. The terminology is active and classified with the semantic type of Injury or Poisoning. Burns generally involve heat, electricity, radiation, or chemicals, and clinical severity ranges from superficial to full-thickness skin damage. 1 2

Plain-language overview

Burns generally happen through direct or indirect contact with heat, electric current, radiation, or chemical agents, and clinical severity ranges from superficial to full-thickness skin damage. 2

This code is an active ICD-10-CM terminology concept with the semantic type of Injury or Poisoning, and it is published with the abbreviation Burn of unspecified degree of left thumb (nail), init encntr. 1

What this code represents

The official preferred name for T23.012A is Burn of unspecified degree of left thumb (nail), initial encounter, and the terminology record explicitly lists its status as active. 1

Code T23.012A is designated as a billable diagnosis code, and it is listed alongside T23.012D for a subsequent encounter of a burn of unspecified degree of the left thumb (nail). 5

Coding details

In the ICD-10-CM hierarchy, T23.012A has the parent concept T23.012, Burn of unspecified degree of left thumb (nail), and the target code itself has narrower subordinate concepts within the terminology. 1

The target code T23.012A applies to an initial encounter, whereas T23.012D represents a subsequent encounter for a burn of unspecified degree of the left thumb (nail). 5

Documentation considerations

The official preferred name for T23.012A explicitly identifies the anatomical site as the left thumb (nail), and the encounter character designates this as an initial encounter. 1

Coverage and utilization context

Medicare billing and coding articles for surgical nail treatment and plastic surgery include specific burn and corrosion codes, such as third-degree burns of fingers and thumbs. 3 4

What the sources add

The National Cancer Institute terminology record establishes the official code label and hierarchical status, while the Codigo billing reference adds the billable specificity and distinguishes the initial encounter from the subsequent encounter code. 1 5

Sources

1. ICD-10-CM T23.012A terminology record — National Cancer Institute Enterprise Vocabulary Services; accessed 2026-07-27.
2. Burns: MedlinePlus Medical Encyclopedia — medlineplus.gov; accessed 2026-07-27.
3. Article - Billing and Coding: Surgical Treatment of Nails (A57666) — cms.gov; accessed 2026-07-27.
4. Article - Billing and Coding: Plastic Surgery (A57222) — cms.gov; accessed 2026-07-27.
5. Codigo. The #1 Billing Agency for Medical Practices — codigo.care; accessed 2026-07-27.