What is ICD-10 code I69.343?

I69.343 is the ICD-10-CM diagnosis code for Monoplegia of lower limb following cerebral infarction affecting right non-dominant side. Weakness or paralysis affecting one leg on the right side of the body after a stroke, in a person whose dominant side is the left. I69.343 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. I69.343 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. I69.343 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. I69.343 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 I69.343?

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 I69.343, V28 maps to Monoplegia, Other Paralytic Syndromes at RAF 0.000 while V24 mapped to Monoplegia, Other Paralytic Syndromes at RAF 0.304. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting I69.343?

Lower limb monoplegia is less common than upper limb; verify the diagnosis carefully Non-dominant side designation indicates the affected side is opposite to the patient's dominant side Because I69.343 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.

I69.343 ICD-10 Code: Monoplegia of lower limb

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 lookupI69.343Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Diseases of the circulatory system (I00-I99) / Cerebrovascular diseases (I60-I69)

I69.343

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

Monoplegia of lower limb following cerebral infarction affecting right non-dominant side

Weakness or paralysis affecting one leg on the right side of the body after a stroke, in a person whose dominant side is the left.

Buddy Insight

CMS-HCC V28

Mapped

HCC 254

Monoplegia, Other Paralytic S...

RAF 0.0

CMS-HCC V24

Mapped

HCC 104

Monoplegia, Other Paralytic S...

RAF 0.304

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Mapped

HCC 104

Monoplegia, Other Paralytic S...

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

I69.3Sequelae of cerebral infarction

I69.34Monoplegia of lower limb following cerebral infarction

I69.343Monoplegia of lower limb following cerebral infarction affecting right non-dominant side

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for I69.343 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for I69.343 in this effective period.

Related Child Codes

Official

I69.341Monoplegia of lower limb following cerebral infarction affecting right dominant side

I69.342Monoplegia of lower limb following cerebral infarction affecting left dominant side

I69.344Monoplegia of lower limb following cerebral infarction affecting left non-dominant side

I69.349Monoplegia of lower limb following cerebral infarction affecting unspecified side

Includes

Official

ICD-10-CM does not list Includes notes for I69.343 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for I69.343 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for I69.343 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for I69.343 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for I69.343 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Documentation of prior cerebral infarction (stroke) as the causative event with clear causal linkage to the current deficit

Confirmation that this is a sequela (late effect), not an acute or current cerebrovascular event

Documentation that paralysis or weakness is isolated to one lower extremity (leg)

Current functional status of the affected lower limb including strength and mobility assessment

MEAT Support

HCC Buddy guidance

Documentation of prior cerebral infarction (stroke) as the causative event with clear causal linkage to the current deficit

Confirmation that this is a sequela (late effect), not an acute or current cerebrovascular event

Documentation that paralysis or weakness is isolated to one lower extremity (leg)

Current functional status of the affected lower limb including strength and mobility assessment

Audit Caution

HCC Buddy guidance

Using an acute cerebrovascular code (I60-I63) instead of a sequela code (I69) when the event occurred in a prior encounter

Coding monoplegia when both limbs on the same side are affected — if both upper and lower extremities are involved, code hemiplegia instead

Failing to distinguish between upper limb monoplegia and lower limb monoplegia, which require different codes

Incorrectly assigning dominant vs non-dominant side — if handedness is not documented, the default assumption is right-hand dominance per ICD-10-CM guidelines

Common Mistakes

HCC Buddy guidance

I69.1/I69.2/I69.8xx codes — sequelae of different cerebrovascular event types; must match the documented causative event

G83.1x (Monoplegia of lower limb, not specified as sequela) — use G83.1 when cause is not cerebrovascular

I69.x5x (Hemiplegia) — if both upper and lower limbs on same side are affected, code hemiplegia instead

Dominant vs non-dominant side codes — verify patient handedness; right-handed patients have right dominant side, left-handed have right non-dominant

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 I69.343 an HCC code?

Yes. I69.343 maps to Monoplegia, Other Paralytic Syndromes under the CMS-HCC V28 risk adjustment model (and Monoplegia, Other Paralytic Syndromes under V24).

HCC Category Mapping

V28HCC 254, Monoplegia, Other Paralytic Syndromes

0.000

V24HCC 104, Monoplegia, Other Paralytic Syndromes

0.304

ESRDHCC 104, Monoplegia, Other Paralytic Syndromes

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 I69.343

For I69.343to 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 I69.343 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

I69.343 is the ICD-10-CM diagnosis code for monoplegia of lower limb following cerebral infarction affecting right non-dominant side. Weakness or paralysis affecting one leg on the right side of the body after a stroke, in a person whose dominant side is the left. I69.343 sits in the ICD-10-CM chapter for diseases of the circulatory system (i00-i99), within the section covering cerebrovascular diseases (i60-i69).

Under the CMS-HCC V28 risk adjustment model, I69.343 maps to Monoplegia, Other Paralytic Syndromes (HCC 254) with a community, non-dual, aged base RAF weight of 0.000. Under the older V24 model, I69.343 mapped to the same category but with a base RAF weight of 0.304, V28 recalibrated weights across the entire model. 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.

Lower limb monoplegia is less common than upper limb; verify the diagnosis carefully. Because I69.343 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 I69.343 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•Lower limb monoplegia is less common than upper limb; verify the diagnosis carefully
•Non-dominant side designation indicates the affected side is opposite to the patient's dominant side

Clinical Significance

Monoplegia of the lower limb as a sequela of a cerebral infarction (ischemic stroke) represents a chronic neurological deficit that significantly impacts the patient's functional status and ongoing care needs. Lower limb monoplegia significantly impacts mobility, increases fall risk, and typically requires physical therapy, assistive devices, and ongoing monitoring. This diagnosis is important for risk adjustment as it indicates persistent functional impairment requiring sustained rehabilitative and medical resources.

Documentation Requirements

✓Documentation of prior cerebral infarction (stroke) as the causative event with clear causal linkage to the current deficit
✓Confirmation that this is a sequela (late effect), not an acute or current cerebrovascular event
✓Documentation that paralysis or weakness is isolated to one lower extremity (leg)
✓Current functional status of the affected lower limb including strength and mobility assessment
✓Documentation of which side is affected (right or left)
✓Documentation of patient's hand dominance to determine dominant vs non-dominant classification
✓Current treatment plan including rehabilitation services, medications, and adaptive equipment
✓Assessment that the condition is being actively monitored or managed during the encounter

Commonly Confused Codes

•I69.1/I69.2/I69.8xx codes: sequelae of different cerebrovascular event types; must match the documented causative event
•G83.1x (Monoplegia of lower limb, not specified as sequela): use G83.1 when cause is not cerebrovascular
•I69.x5x (Hemiplegia): if both upper and lower limbs on same side are affected, code hemiplegia instead
•Dominant vs non-dominant side codes: verify patient handedness; right-handed patients have right dominant side, left-handed have right non-dominant