What is ICD-10 code L89.524?

L89.524 is the ICD-10-CM diagnosis code for Pressure ulcer of left ankle, stage 4. A stage 4 pressure ulcer on the left ankle with full-thickness skin loss and exposed bone, tendon, or muscle tissue. L89.524 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. L89.524 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. L89.524 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. L89.524 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 L89.524?

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 L89.524, V28 maps to Pressure Ulcer of Skin with Full Thickness Skin Loss at RAF 0.662 while V24 mapped to Pressure Ulcer of Skin with Necrosis Through to Muscle, Tendon, or Bone at RAF 1.071. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting L89.524?

Stage 4 is the most severe; requires explicit documentation of exposed bone, cartilage, or muscle in the wound bed Confirm laterality (left ankle) and document any complications such as infection or osteomyelitis separately Because L89.524 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.

L89.524 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 lookupL89.524Effective 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)

L89.524

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

Pressure ulcer of left ankle, stage 4

A stage 4 pressure ulcer on the left ankle with full-thickness skin loss and exposed bone, tendon, or muscle tissue.

Buddy Insight

A stage 4 pressure ulcer of the left ankle is the most severe stage, with full thickness tissue loss exposing bone, tendon, or muscle.

CMS-HCC V28

Mapped

HCC 379

Pressure Ulcer of Skin with F...

RAF 0.662

CMS-HCC V24

Mapped

HCC 157

Pressure Ulcer of Skin with N...

RAF 1.071

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Mapped

HCC 157

Pressure Ulcer of Skin with N...

RAF 0.0

RXHCC

Not risk-adjusted for this model/period.

RAF 0

Code Trumping

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Code Book Path

Official

L89.5Pressure ulcer of ankle

L89.52Pressure ulcer of left ankle

L89.524Pressure ulcer of left ankle, stage 4

Inclusion Terms

Official

Healing pressure ulcer of left ankle, stage 4
Pressure ulcer with necrosis of soft tissues through to underlying muscle, tendon, or bone, left ankle

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for L89.524 in this effective period.

Related Child Codes

Official

L89.520Pressure ulcer of left ankle, unstageable

L89.521Pressure ulcer of left ankle, stage 1

L89.522Pressure ulcer of left ankle, stage 2

L89.523Pressure ulcer of left ankle, stage 3

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

Includes

Official

ICD-10-CM does not list Includes notes for L89.524 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for L89.524 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for L89.524 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for L89.524 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for L89.524 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Exact anatomical location with laterality

Explicit staging as stage 4 by the treating provider

Documentation of exposed structures (bone, tendon, muscle, joint capsule)

Wound dimensions: length x width x depth in centimeters

MEAT Support

HCC Buddy guidance

Exact anatomical location with laterality

Explicit staging as stage 4 by the treating provider

Documentation of exposed structures (bone, tendon, muscle, joint capsule)

Wound dimensions: length x width x depth in centimeters

Audit Caution

HCC Buddy guidance

Confirm provider explicitly documents stage 4 — coders cannot interpret wound depth from clinical descriptions alone

If eschar or slough obscures the wound base, code as unstageable rather than stage 4

Stage 4 pressure ulcers may also require coding for osteomyelitis (M86.x) or cellulitis (L03.x) if those conditions are separately documented

Never reverse-stage a healing stage 4 ulcer to stage 3 or 2; it remains 'healing stage 4'

Common Mistakes

HCC Buddy guidance

L89.523 — Stage 3 of left ankle has subcutaneous tissue visible but NO exposed bone, tendon, or muscle

L89.520 — Unstageable of left ankle means the wound base is covered by slough or eschar

M86.x — Osteomyelitis should be coded separately when documented as complication of stage 4 pressure ulcer

L97.xxx — Non-pressure chronic ulcers have different etiology (venous, arterial, diabetic); verify pressure as the cause

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 L89.524 an HCC code?

Yes. L89.524 maps to Pressure Ulcer of Skin with Full Thickness Skin Loss under the CMS-HCC V28 risk adjustment model (and Pressure Ulcer of Skin with Necrosis Through to Muscle, Tendon, or Bone under V24).

HCC Category Mapping

V28HCC 379, Pressure Ulcer of Skin with Full Thickness Skin Loss

0.662

V24HCC 157, Pressure Ulcer of Skin with Necrosis Through to Muscle, Tendon, or Bone

1.071

ESRDHCC 157, Pressure Ulcer of Skin with Necrosis Through to Muscle, Tendon, or Bone

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 L89.524

For L89.524to 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 L89.524 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

L89.524 is the ICD-10-CM diagnosis code for pressure ulcer of left ankle, stage 4. A stage 4 pressure ulcer on the left ankle with full-thickness skin loss and exposed bone, tendon, or muscle tissue. L89.524 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, L89.524 maps to Pressure Ulcer of Skin with Full Thickness Skin Loss (HCC 379) with a community, non-dual, aged base RAF weight of 0.662. Under the older CMS-HCC V24 model, L89.524 maps to Pressure Ulcer of Skin with Necrosis Through to Muscle, Tendon, or Bone (HCC 157) with a community, non-dual, aged base RAF weight of 1.071. 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.

Stage 4 is the most severe; requires explicit documentation of exposed bone, cartilage, or muscle in the wound bed. Because L89.524 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 L89.524 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Stage 4 is the most severe; requires explicit documentation of exposed bone, cartilage, or muscle in the wound bed
•Confirm laterality (left ankle) and document any complications such as infection or osteomyelitis separately

Clinical Significance

A stage 4 pressure ulcer of the left ankle is the most severe stage, with full thickness tissue loss exposing bone, tendon, or muscle. These wounds carry the highest morbidity risk including osteomyelitis, sepsis, and significant mortality, demanding complex interdisciplinary wound care. Stage 4 pressure ulcers have the highest risk adjustment impact in this category, mapping to V28 HCC 379 (RAF 0.662) and V24 HCC 157 (RAF 1.071), reflecting the extreme clinical complexity and cost of care.

Documentation Requirements

✓Exact anatomical location with laterality
✓Explicit staging as stage 4 by the treating provider
✓Documentation of exposed structures (bone, tendon, muscle, joint capsule)
✓Wound dimensions: length x width x depth in centimeters
✓Presence and measurements of undermining, tunneling, or sinus tracts
✓Wound bed description including necrotic tissue, slough, granulation tissue percentages
✓Wound drainage characteristics (type, volume, color, odor)
✓Signs of infection or osteomyelitis (bone involvement, positive cultures)
✓Comprehensive treatment plan including surgical consultation, debridement, negative pressure wound therapy, flap/graft considerations
✓Nutritional assessment with albumin/prealbumin levels and dietary interventions
✓Pressure redistribution strategy (specialty mattress, turning schedule, offloading devices)

Commonly Confused Codes

•L89.523: Stage 3 of left ankle has subcutaneous tissue visible but NO exposed bone, tendon, or muscle
•L89.520: Unstageable of left ankle means the wound base is covered by slough or eschar
•M86.x: Osteomyelitis should be coded separately when documented as complication of stage 4 pressure ulcer
•L97.xxx: Non-pressure chronic ulcers have different etiology (venous, arterial, diabetic); verify pressure as the cause