What is ICD-10 code L89.520?

L89.520 is the ICD-10-CM diagnosis code for Pressure ulcer of left ankle, unstageable. A pressure sore on the left ankle that cannot be staged or classified into standard severity levels, often due to eschar, slough, or inability to assess the wound. L89.520 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. L89.520 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. L89.520 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. L89.520 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

What is the V28 vs V24 difference for L89.520?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. For L89.520, V28 maps to Pressure Ulcer of Skin, Unstageable/Unspecified at RAF 0.000 while V24 mapped to Pressure Ulcer of Skin with Full Thickness Skin Loss at RAF 0.662. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting L89.520?

Document the reason the ulcer is unstageable (e.g., covered with eschar, too much drainage) in the medical record If the stage becomes determinable after eschar removal or further assessment, update the code accordingly Because L89.520 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

L89.520 ICD-10 Code: Pressure ulcer of left ankle

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupL89.520Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the skin and subcutaneous tissue (L00-L99) / Other disorders of the skin and subcutaneous tissue (L80-L99)

L89.520

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Pressure ulcer of left ankle, unstageable

A pressure sore on the left ankle that cannot be staged or classified into standard severity levels, often due to eschar, slough, or inability to assess the wound.

Buddy Insight

An unstageable pressure ulcer of the left ankle indicates wound depth cannot be determined due to slough or eschar covering the wound bed.

CMS-HCC V28

Mapped

HCC 381

Pressure Ulcer of Skin, Unsta...

RAF 0.0

CMS-HCC V24

Mapped

HCC 158

Pressure Ulcer of Skin with F...

RAF 0.662

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Mapped

HCC 158

Pressure Ulcer of Skin with F...

RAF 0.0

RXHCC

Not risk-adjusted for this model/period.

RAF 0

Code Trumping

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Compare selected patient codes to show trumped or trumps impact.

Code Book Path

Official

L89.5Pressure ulcer of ankle

L89.52Pressure ulcer of left ankle

L89.520Pressure ulcer of left ankle, unstageable

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for L89.520 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for L89.520 in this effective period.

Related Child Codes

Official

L89.521Pressure ulcer of left ankle, stage 1

L89.522Pressure ulcer of left ankle, stage 2

L89.523Pressure ulcer of left ankle, stage 3

L89.524Pressure ulcer of left ankle, stage 4

L89.526Pressure-induced deep tissue damage of left ankle

Includes

Official

ICD-10-CM does not list Includes notes for L89.520 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for L89.520 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for L89.520 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for L89.520 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for L89.520 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Exact anatomical location of the pressure ulcer

Description of wound bed including presence of slough, eschar, or necrotic tissue preventing staging

Clinical reasoning for why the ulcer cannot be staged (e.g., wound bed obscured by eschar)

Wound dimensions (length x width) if measurable

MEAT Support

HCC Buddy guidance

Exact anatomical location of the pressure ulcer

Description of wound bed including presence of slough, eschar, or necrotic tissue preventing staging

Clinical reasoning for why the ulcer cannot be staged (e.g., wound bed obscured by eschar)

Wound dimensions (length x width) if measurable

Audit Caution

HCC Buddy guidance

Do not assign unstageable when the wound simply has not been assessed — unstageable means it was evaluated but the base cannot be visualized

Unstageable is NOT the same as 'unknown stage' — if documentation lacks any staging information, query the provider

Do not assign stage 1 (L89.x10 not valid for HCC) when the wound has slough — slough indicates at least stage 3

Ensure laterality is documented; unspecified codes should only be used when the provider truly does not specify

Common Mistakes

HCC Buddy guidance

L89.514 — Stage 4 pressure ulcer of left ankle has a visible wound bed and can be staged; unstageable cannot

L89.520 — Pressure ulcer of right ankle, unstageable; laterality matters for code selection

L97.919 — Non-pressure chronic ulcer of ankle is NOT caused by pressure/shearing forces; verify etiology

L89.90 — Unspecified site pressure ulcer should only be used when location is truly undocumented

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is L89.520 an HCC code?

Yes. L89.520 maps to Pressure Ulcer of Skin, Unstageable/Unspecified under the CMS-HCC V28 risk adjustment model (and Pressure Ulcer of Skin with Full Thickness Skin Loss under V24).

HCC Category Mapping

V28HCC 381, Pressure Ulcer of Skin, Unstageable/Unspecified

0.000

V24HCC 158, Pressure Ulcer of Skin with Full Thickness Skin Loss

0.662

ESRDHCC 158, Pressure Ulcer of Skin with Full Thickness Skin Loss

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for L89.520

For L89.520to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed L89.520 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

L89.520 is the ICD-10-CM diagnosis code for pressure ulcer of left ankle, unstageable. A pressure sore on the left ankle that cannot be staged or classified into standard severity levels, often due to eschar, slough, or inability to assess the wound. L89.520 sits in the ICD-10-CM chapter for diseases of the skin and subcutaneous tissue (l00-l99), within the section covering other disorders of the skin and subcutaneous tissue (l80-l99).

Under the CMS-HCC V28 risk adjustment model, L89.520 maps to Pressure Ulcer of Skin, Unstageable/Unspecified (HCC 381) with a community, non-dual, aged base RAF weight of 0.000. Under the older CMS-HCC V24 model, L89.520 maps to Pressure Ulcer of Skin with Full Thickness Skin Loss (HCC 158) with a community, non-dual, aged base RAF weight of 0.662. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

Document the reason the ulcer is unstageable (e.g., covered with eschar, too much drainage) in the medical record. Because L89.520 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for L89.520 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Document the reason the ulcer is unstageable (e.g., covered with eschar, too much drainage) in the medical record
•If the stage becomes determinable after eschar removal or further assessment, update the code accordingly

Clinical Significance

An unstageable pressure ulcer of the left ankle indicates wound depth cannot be determined due to slough or eschar covering the wound bed. This is clinically significant because it suggests at least a stage 3 or 4 ulcer beneath the obscuring tissue, reflecting substantial tissue damage and high resource utilization. Risk adjustment captures these as high-acuity skin conditions requiring intensive wound care management.

Documentation Requirements

✓Exact anatomical location of the pressure ulcer
✓Description of wound bed including presence of slough, eschar, or necrotic tissue preventing staging
✓Clinical reasoning for why the ulcer cannot be staged (e.g., wound bed obscured by eschar)
✓Wound dimensions (length x width) if measurable
✓Current treatment plan including wound care modality and dressing type
✓Assessment of surrounding skin (maceration, induration, erythema)
✓Etiology of pressure (immobility, positioning, medical device)
✓Presence or absence of infection signs

Commonly Confused Codes

•L89.514: Stage 4 pressure ulcer of left ankle has a visible wound bed and can be staged; unstageable cannot
•L89.520: Pressure ulcer of right ankle, unstageable; laterality matters for code selection
•L97.919: Non-pressure chronic ulcer of ankle is NOT caused by pressure/shearing forces; verify etiology
•L89.90: Unspecified site pressure ulcer should only be used when location is truly undocumented