Code structure of category L89 – Pressure ulcer

The codes for pressure ulcers and non-pressure chronic ulcers are located in ICD-10 chapter 12, Diseases of the skin and subcutaneous tissue (L00-L99). Pressure ulcer codes fall under category L89 and non-pressure chronic ulcer fall under category L97. This article is emphasized on pressure ulcer coding structure and its documentation requirements.

Pressure Ulcer:

Definition: “Localized injury to the skin and/or underlying tissue, usually over a bony prominence, as a result of intense and/or prolonged pressure, or pressure in combination with shear. The pressure ulcer/injury can present as intact skin or an open ulcer and may be painful”.

Pressure ulcer codes (category L89) are combination codes that identify the

  • the site of the ulcer,
  • laterality and
  • Stage of the pressure ulcer.

Here is the break up for the category L89:

Site of the Ulcer:

The fourth character in category L89 represents the site of the pressure ulcer. Below table lists the code category and the appropriate anatomic site of the ulcer.

Watch for the instructional note:

When you start assigning codes for pressure ulcer, you should remember the instructional note under the category L89. The note guides you to code first any associated gangrene from category I96.

Multiple sites coding:

It is appropriate to assign as many codes from category L89 as needed to identify all pressure ulcers that the patient has received treatment. In case of multiple sites, the sequencing will be based on the severity and the most severe stage would qualify for the primary diagnosis.

Other and unspecified pressure ulcer site:

Do not confuse with the terms “other” and “unspecified” when documented for the pressure ulcer sites.

You should code L89.89 (Pressure ulcer of other site) when the provider has documented the site of the ulcer, but there is no specific code under L89 to specify the documented site.

You should code L89.9 (Pressure ulcer of unspecified site) when the provider has not documented the ulcer site. This code should be rarely used and it is necessary to educate the physicians to document the site if missing in the medical record.


The fifth character in category L89 represents the laterality and you can choose the codes for right, left and unspecified anatomic areas of the specified pressure ulcer site. However there are no bilateral codes available in the L89 section of ICD-10. Therefore if the pressure ulcer affects both the right and left side of the pressure ulcers, such as hip ulcer, then you need to report separate codes for the right and left as appropriate.

Stage of the ulcer:

The sixth character represents the stage which correlates with the severity of the condition. These stages are defined by the National Pressure Ulcer Advisory Panel (NPUAP). Previously there were four stages (stage 1 to stage 4) but later on, these stages were revised and categories deep tissue injury and unstageablewere added to it.

Stage 1 – Intact skin with non-blanchable redness of a localized area, usually over a bony prominence. Often resolve on their own and usually found on the heels or sacral area.

Stage 2: Refers to partial thickness loss of skin with exposed dermis. The wound bed is viable, pink or red, moist, and may also present as an intact or ruptured serum-filled blister.

Stage 3: This kind of injury involves full-thickness loss of skin, exposing adipose tissue in the ulcer and often involving granulation tissue and epibole (i.e., rolled wound edges). Tunnels slough, and eschar may also be visible, although bone, tendon, and muscle are not exposed.

Stage 4: This stage involves Full-thickness skin and tissue loss with exposed or directly palpable fascia, muscle, tendon, ligament, cartilage or bone in the ulcer. Depth varies by anatomical location, but slough, eschar, epibole, and tunneling often occur.

Unstageable: Full-thickness skin and tissue loss in which the extent of tissue damage within the ulcer cannot be confirmed because it is obscured by slough or eschar. If slough or eschar is removed, a Stage 3 or Stage 4 pressure injury will be revealed.

Deep tissue injury: This is another stage defined by NPUAP based on the damage to the underlying tissue.

How to recognize a deep tissue injury (DTI)?

  • Signs include intact or non-intact skin with localized area of persistent non-blanchable deep red, maroon, purple discoloration or a blood filled blister that forms due to shear and/or pressure.
  • Prior to the identification of the discoloured area, the skin may feel boggy, firm, mushy, painful, cooler or warmer than the surrounding skin.
  • the wound may progress to a thin blister overlaying a dark wound bed, which may eventually be covered by eschar
  • additional tissue layers may become rapidly exposed even with optimal treatment

New codes for deep tissue injury

There is an important change that you need to understand regarding “deep tissue injury. Prior to the 2020 ICD-10-CM release, deep tissue injuries were indexed to ulcer, pressure, unstageable and then by site. This led to a contradiction when AHRQ (Agency for health research and Quality) proposed the clinical differences between unstageable pressure ulcer and deep tissue injury. Also AHRQ reasoned that unstageable ulcers can only be stage 3 or stage 4 which involves tissue loss by definition and deep tissue injury may resolve without any tissue loss. Therefore ICD-10 CM expanded the category L89 ((L89.–6).) to include specific new codes for deep tissue pressure injury effective from October 1, 2019.

Example: ICD-10 CM codes for deep pressure injury:

Documentation requirements:

Diagnosis by Physician: If a patient has pressure ulcer, the diagnosis needs to be made by a physician or licensed independent practitioner. You are allowed to use the nursing or wound care documentation to code pressure ulcers completely such as to determine the stage, but the diagnosis should be strictly made by the physician.

Match with NPUAP definitions: If the provider does not document the specific pressure ulcer stage, then you should check the documentation for the language that matches with the NPUAP definitions for the particular stage assignment.

Happy learning! Happy coding!


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