What is ICD-10 code G72.41?

G72.41 is the ICD-10-CM diagnosis code for Inclusion body myositis [IBM]. It belongs to the ICD-10-CM chapter for diseases of the nervous system (g00-g99). G72.41 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. G72.41 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. G72.41 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. G72.41 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 G72.41?

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. G72.41 is a payment HCC under V28 (Rheumatoid Arthritis and Inflammatory Connective Tissue Disease) but was not retained as a payment HCC under V24. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting G72.41?

IBM is a specific form of myositis with distinct pathological findings; ensure documentation clearly distinguishes it from other myositis types (polymyositis, dermatomyositis) before coding This code should be paired with appropriate manifestation codes for muscle weakness or other complications if documented, and consider adding laterality codes if the condition affects specific limbs asymmetrically Because G72.41 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.

G72.41 ICD-10 Code: Inclusion body myositis [IBM]

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 lookupG72.41Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the nervous system (G00-G99) / Diseases of myoneural junction and muscle (G70-G73)

G72.41

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

Inclusion body myositis [IBM]

Inclusion body myositis is a rare muscle disease where the muscles gradually weaken and waste away, caused by abnormal protein deposits forming inside muscle cells. It primarily affects older adults and causes progressive weakness in the legs and arms.

Buddy Insight

Inclusion body myositis is the most common acquired myopathy in patients over age 50, causing progressive asymmetric weakness particularly in finger flexors and quadriceps.

CMS-HCC V28

Mapped

HCC 93

Rheumatoid Arthritis and Infl...

RAF 0.175

CMS-HCC V24

Not risk-adjusted for this model/period.

RAF 0

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Not risk-adjusted for this model/period.

RAF 0

RXHCC

Not risk-adjusted for this model/period.

RAF 0

Code Trumping

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Code Book Path

Official

G72Other and unspecified myopathies

G72.4Inflammatory and immune myopathies, not elsewhere classified

G72.41Inclusion body myositis [IBM]

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for G72.41 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for G72.41 in this effective period.

Related Child Codes

Official

G72.49Other inflammatory and immune myopathies, not elsewhere classified

Includes

Official

ICD-10-CM does not list Includes notes for G72.41 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for G72.41 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for G72.41 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for G72.41 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for G72.41 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Muscle biopsy showing characteristic rimmed vacuoles and endomysial inflammation with invasion of non-necrotic fibers

Clinical presentation: asymmetric weakness, finger flexion weakness, quadriceps weakness, dysphagia

Elevated or normal creatine kinase levels

Age of onset (typically >50 years)

MEAT Support

HCC Buddy guidance

Muscle biopsy showing characteristic rimmed vacuoles and endomysial inflammation with invasion of non-necrotic fibers

Clinical presentation: asymmetric weakness, finger flexion weakness, quadriceps weakness, dysphagia

Elevated or normal creatine kinase levels

Age of onset (typically >50 years)

Audit Caution

HCC Buddy guidance

Coding as polymyositis (M33.20) instead of inclusion body myositis when biopsy shows rimmed vacuoles — these have very different prognoses and treatment responses

Missing the diagnosis when a patient with refractory polymyositis actually has inclusion body myositis

Not coding dysphagia separately when it is a documented complication

Failing to recognize the asymmetric pattern (finger flexors, quadriceps) that distinguishes inclusion body myositis from other myopathies

Common Mistakes

HCC Buddy guidance

M33.20 — Polymyositis is a different inflammatory myopathy that responds to immunosuppression; inclusion body myositis typically does not

M33.10 — Dermatomyositis has characteristic skin findings absent in inclusion body myositis

G72.49 — Other inflammatory and immune myopathies should not be used when inclusion body myositis is confirmed

G71.09 — Other specified muscular dystrophies is for genetic dystrophies, not acquired inflammatory myositis

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 G72.41 an HCC code?

Yes. G72.41 maps to Rheumatoid Arthritis and Inflammatory Connective Tissue Disease under the CMS-HCC V28 risk adjustment model.

HCC Category Mapping

V28HCC 93, Rheumatoid Arthritis and Inflammatory Connective Tissue Disease

0.175

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 G72.41

For G72.41to 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 G72.41 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

G72.41 is the ICD-10-CM diagnosis code for inclusion body myositis [ibm]. Inclusion body myositis is a rare muscle disease where the muscles gradually weaken and waste away, caused by abnormal protein deposits forming inside muscle cells. It primarily affects older adults and causes progressive weakness in the legs and arms. G72.41 sits in the ICD-10-CM chapter for diseases of the nervous system (g00-g99), within the section covering diseases of myoneural junction and muscle (g70-g73).

Under the CMS-HCC V28 risk adjustment model, G72.41 maps to Rheumatoid Arthritis and Inflammatory Connective Tissue Disease (HCC 93) with a community, non-dual, aged base RAF weight of 0.175. G72.41 was not retained as a payment HCC under the older V24 model, so V28 introduced or recategorized it during the 2024–2026 phase-in. 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.

IBM is a specific form of myositis with distinct pathological findings; ensure documentation clearly distinguishes it from other myositis types (polymyositis, dermatomyositis) before coding. Because G72.41 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 G72.41 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•IBM is a specific form of myositis with distinct pathological findings; ensure documentation clearly distinguishes it from other myositis types (polymyositis, dermatomyositis) before coding
•This code should be paired with appropriate manifestation codes for muscle weakness or other complications if documented, and consider adding laterality codes if the condition affects specific limbs asymmetrically

Clinical Significance

Inclusion body myositis is the most common acquired myopathy in patients over age 50, causing progressive asymmetric weakness particularly in finger flexors and quadriceps. Unlike other inflammatory myopathies, it is typically resistant to immunosuppressive therapy. Accurate coding is critical for distinguishing this treatment-resistant condition from treatable polymyositis and for reflecting the progressive disability in risk adjustment.

Documentation Requirements

✓Muscle biopsy showing characteristic rimmed vacuoles and endomysial inflammation with invasion of non-necrotic fibers
✓Clinical presentation: asymmetric weakness, finger flexion weakness, quadriceps weakness, dysphagia
✓Elevated or normal creatine kinase levels
✓Age of onset (typically >50 years)
✓Response to immunosuppressive therapy (typically poor in inclusion body myositis)
✓Provider's explicit diagnosis of inclusion body myositis, distinguished from polymyositis

Commonly Confused Codes

•M33.20: Polymyositis is a different inflammatory myopathy that responds to immunosuppression; inclusion body myositis typically does not
•M33.10: Dermatomyositis has characteristic skin findings absent in inclusion body myositis
•G72.49: Other inflammatory and immune myopathies should not be used when inclusion body myositis is confirmed
•G71.09: Other specified muscular dystrophies is for genetic dystrophies, not acquired inflammatory myositis