Skip to content
HCC Buddy home

M89.642 ICD-10-CM Code: Osteopathy after poliomyelitis, left hand

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.

FY 2026 Apr update / Diseases of the musculoskeletal system and connective tissue (M00-M99) / Other osteopathies (M86-M90)

M89.642

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

Osteopathy after poliomyelitis, left hand

Bone disease that develops as a long-term consequence of polio infection, affecting the left hand.

Buddy the Bee presenting code insight

Buddy Insight

Left hand post-polio osteopathy involves chronic bone deterioration in the left hand as a late consequence of poliomyelitis infection, potentially severely compromising hand function and independence in daily activities.

CMS-HCC V28

HCC 92

RAF 0.479

CMS-HCC V24

HCC 39

RAF 0.401

ACA/HHS

HCC 55

Varies by metal level

ESRD/PACE

HCC 39

RAF 0.092

RXHCC

N/A

—

Not mapped

Code Book Path

Official
M89.6Osteopathy after poliomyelitis
M89.64Osteopathy after poliomyelitis, hand
M89.642Osteopathy after poliomyelitis, left hand

Inclusion Terms

Official

ICD-10-CM does not list inclusion terms for M89.642 in this effective period.

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for M89.642 in this effective period.

Related Child Codes

Official
M89.641Osteopathy after poliomyelitis, right hand
M89.649Osteopathy after poliomyelitis, unspecified hand

Includes

Official

ICD-10-CM does not list Includes notes for M89.642 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for M89.642 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for M89.642 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for M89.642 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for M89.642 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance
Clear history of previous poliomyelitis infection
Specific documentation of left hand bone involvement
Current imaging showing post-polio changes in hand bones
Left hand functional capacity evaluation

MEAT Support

HCC Buddy guidance
Clear history of previous poliomyelitis infection
Specific documentation of left hand bone involvement
Current imaging showing post-polio changes in hand bones
Left hand functional capacity evaluation

Audit Caution

HCC Buddy guidance
Mixing up neurological versus bone manifestations of post-polio complications
Confusing left and right hand laterality
Missing the historical connection to poliomyelitis infection
Incorrectly coding as acute trauma or primary degenerative disease

Common Mistakes

HCC Buddy guidance
G14 — Post-polio syndrome primarily neurological, not bone-related
M25.542 — Left hand pain is symptomatic presentation only
S62.602A — Hand fracture represents acute trauma
M19.042 — Primary hand osteoarthritis lacks post-infectious etiology

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is M89.642 an HCC code?

Yes. M89.642 (Osteopathy after poliomyelitis, left hand) maps to Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis under the CMS-HCC V28 risk adjustment model (and Bone/Joint/Muscle Infections/Necrosis under V24), with a community non-dual aged RAF of 0.479. It is billable for payment year 2026.

Coder answer: M89.642 is billable and maps to V28 HCC 92, Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis. Open it in the Code Book for the tabular path, RAF, and MEAT checklist.

Code
M89.642
Description
Osteopathy after poliomyelitis, left hand
HCC (V28)
HCC 92 — Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis
RAF
0.479
Billable
Yes
Payment year
2026

HCC Category Mapping

V28HCC 92, Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis
0.479
V24HCC 39, Bone/Joint/Muscle Infections/Necrosis
0.401
ESRDHCC 39, Bone/Joint/Muscle Infections/Necrosis
0.092

Each model's RAF is its CMS base weight for that model's standard population, so weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. 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.

Work M89.642 in the Code Book — tabular path, V28 RAF, and MEAT checklist →

MEAT Criteria for M89.642

For M89.642 to 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 M89.642 during that encounter, not just copy-forwarded from a problem list.

Coder workflow notes

Get the V28 RAF + MEAT cheat sheet

One printable page: confirm a code's V28 HCC status, its RAF weight, and the MEAT your note needs to make it stick. Free, no card.

Free PDF. No card. Unsubscribe anytime.

What This Code Means

M89.642 is the ICD-10-CM diagnosis code for osteopathy after poliomyelitis, left hand. Bone disease that develops as a long-term consequence of polio infection, affecting the left hand. M89.642 sits in the ICD-10-CM chapter for diseases of the musculoskeletal system and connective tissue (m00-m99), within the section covering other osteopathies (m86-m90).

Under the CMS-HCC V28 risk adjustment model, M89.642 maps to Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis (HCC 92) with a community, non-dual, aged base RAF weight of 0.479. Under the older CMS-HCC V24 model, M89.642 maps to Bone/Joint/Muscle Infections/Necrosis (HCC 39) with a community, non-dual, aged base RAF weight of 0.401. 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.

This code is used for post-polio sequelae affecting bone structure; ensure polio history is documented. Because M89.642 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 M89.642 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

  • •This code is used for post-polio sequelae affecting bone structure; ensure polio history is documented
  • •Verify laterality is clearly documented as left before assigning this code

Clinical Significance

Left hand post-polio osteopathy involves chronic bone deterioration in the left hand as a late consequence of poliomyelitis infection, potentially severely compromising hand function and independence in daily activities. This represents a functionally significant long-term sequela.

Documentation Requirements

  • ✓Clear history of previous poliomyelitis infection
  • ✓Specific documentation of left hand bone involvement
  • ✓Current imaging showing post-polio changes in hand bones
  • ✓Left hand functional capacity evaluation
  • ✓Grip and pinch strength testing
  • ✓Fine motor coordination assessment
  • ✓Impact on activities of daily living and independence
  • ✓Hand therapy and adaptive equipment recommendations

Commonly Confused Codes

  • •G14: Post-polio syndrome primarily neurological, not bone-related
  • •M25.542: Left hand pain is symptomatic presentation only
  • •S62.602A: Hand fracture represents acute trauma
  • •M19.042: Primary hand osteoarthritis lacks post-infectious etiology
  • •M87.842: Other osteonecrosis has different underlying mechanism

Child Codes

M89.641Osteopathy after poliomyelitis, right hand
HCC 92
M89.642Osteopathy after poliomyelitis, left hand
HCC 92
M89.649Osteopathy after poliomyelitis, unspecified hand
HCC 92

Code Hierarchy

└M89Other disorders of bone└M89.6Osteopathy after poliomyelitis└M89.64Osteopathy after poliomyelitis, hand└M89.642Osteopathy after poliomyelitis, left hand
└M89.642Osteopathy after poliomyelitis, left hand

Because M89.642 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.

M89.642 maps to CMS-HCC V28 category 92, Bone/Joint/Muscle/Severe Soft Tissue Infections/Necrosis. See the ICD-10 to HCC mapping hub for how the V28 crosswalk works. Because M89.642 carries a payment HCC, you can see what it adds to a RAF score and check the documentation the chart needs before it is submitted.

Work M89.642 in HCC Buddy

Open M89.642 in the Code Book for the full Index-to-Tabular path, MEAT checklist, and V28 HCC mapping, or in the Encoder to code from a keyword search. Pro includes 7 days to try everything, no card required.

Open in Code BookOpen in EncoderStart Pro