Loading...

    Explore
    • Policy Monitoring
    • Live Policy Feed
    • Billing Codes
    • NPI Medicare & Medicaid
    • Healthcare Providers
    • Health Insurance Payers
    • States
    • Service Lines
    • Taxonomy Codes
    Lookup tools
    • Billing Code Lookup
    • CPT Modifier Lookup
    • Provider Taxonomy Code Lookup
    • Healthcare Provider & Facility Lookup
    • Health Insurance Payer Lookup
    • Payer Contact Directory

    Policy & Benchmark Tools

    • Prior Authorization Lookup
    • Coverage Criteria Lookup
    • Timely Filing Lookup
    • Billing Code Reimbursement Rates
    • Payer Comparison Dashboard
    • Facility Comparison Dashboard
    • All tools

    Company

    • About OpenPayer
    • Data Sources
    • Trek Health
    OpenPayerby Trek Health
    LinkedInYouTube

    © 2026 Trek Health. All rights reserved.

    OpenPayer is built and maintained by Trek Health.

    v1.0.28
    OpenPayerBilling CodesOther joint disordersICD-10-CM m20-acquired-deformities-fingers-toes
    Ask Trek AI about this page

    ICD-10-CM Code For Acquired Deformities Of Fingers And Toes: Group Overview

    The International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM) code group M20 includes acquired deformities of fingers and toes such as hammer toe, mallet toe, and other postnatal digit deformities resulting from trauma, degenerative changes, or biomechanical causes. These ICD-10-CM diagnosis codes are used to document the specific digit affected, laterality, and the clinical severity or complications when applicable, capturing surgical and conservative management scenarios. Accurate coding within the ICD-10-CM M20 group supports proper claim adjudication and complete clinical documentation for appropriate reimbursement.

    Customize your policy alerts

    Sign up for ICD-10-CM Code For Acquired Deformities Of Fingers And Toes: Group Overview policy alerts

    Get alerted when relevant policies change without checking for updates manually.

    Monitor payer policy activity

    Receive email alerts as soon as relevant payer policies are published or updated.

    ICD-10-CM M20: Acquired Deformities Of Fingers And Toes Overview

    The ICD-10-CM M20 group includes acquired deformities affecting the digits, such as hammer toe, mallet toe, and other deformities of fingers and toes that develop after birth due to trauma, disease, or chronic mechanical stress. These diagnoses target the musculoskeletal system, specifically the digits and their soft tissues and joints. Accurate coding matters for proper clinical documentation and supports appropriate reimbursement by reflecting the correct diagnosis and complexity of care.

    Table of contents

    Progress1 / 6

    Explore openpayer tools

    • Billing CodesCPT, HCPCS, DRG & more
    • Reimbursement RatesCommercial vs. Medicare rate reports
    • ProvidersHospitals & facilities
    • PayersPlans & market footprint
    • Taxonomy CodesNUCC specialty codes
    • ModifiersCPT modifiers & usage
    • Prior AuthorizationPA policies by payer & drug
    • Timely FilingFiling deadlines by payer
    • Coverage CriteriaMedical necessity by payer
    • Payer ContactsClaims, PA & appeals contacts
    View all tools

    When to Use

    Use a code from this group when clinical documentation indicates an acquired deformity of a finger or toe, including deformities due to trauma, chronic pressure, or degenerative processes. Select the most specific code available to reflect the exact deformity, affected digit, and laterality to support accurate recordkeeping and billing.

    ICD-10-CM Codes

    33 rows

    ICD-10-CM CodeDescription
    M20.001Unspecified deformity of right finger(s)
    M20.002Unspecified deformity of left finger(s)
    M20.009Unspecified deformity of unspecified finger(s)
    M20.011Mallet finger of right finger(s)
    M20.012Mallet finger of left finger(s)
    M20.019Mallet finger of unspecified finger(s)
    M20.021Boutonniere deformity of right finger(s)
    M20.022Boutonniere deformity of left finger(s)
    M20.029Boutonniere deformity of unspecified finger(s)
    M20.031Swan-neck deformity of right finger(s)
    M20.032Swan-neck deformity of left finger(s)
    M20.039Swan-neck deformity of unspecified finger(s)
    M20.091Other deformity of right finger(s)
    M20.092Other deformity of left finger(s)
    M20.099Other deformity of finger(s), unspecified finger(s)
    M20.10Hallux valgus (acquired), unspecified foot
    M20.11Hallux valgus (acquired), right foot
    M20.12Hallux valgus (acquired), left foot
    M20.20Hallux rigidus, unspecified foot
    M20.21Hallux rigidus, right foot

    Showing 1–20 of 33

    DRG Codes

    3 rows

    DRG CodeDescription
    564Other Musculoskeletal System and Connective Tissue Diagnoses with MCC
    565Other Musculoskeletal System and Connective Tissue Diagnoses with CC
    566Other Musculoskeletal System and Connective Tissue Diagnoses without CC/MCC

    Typical Clinical Scenarios

    • An elderly patient with progressive medial deviation of the great toe causing persistent forefoot pain and difficulty fitting shoes presents to clinic for evaluation and conservative management; exam shows hallux valgus with a prominent bunion and lateral deviation of the distal phalanx. A diagnosis from this group is assigned to capture the acquired angular deformity of the toe contributing to mechanical symptoms and footwear intolerance. Typical codes: M20.11, M20.12
    • A middle-aged manual laborer attends urgent care after sustaining a crush injury to the distal phalanx of the index finger at work; there is flexion deformity and limited extension of the proximal interphalangeal joint developing over days with palpable joint stiffness. A code from this group is used to describe the acquired flexion contracture/triggering deformity of the finger as a complication of the traumatic injury and soft-tissue damage. Typical codes: M20.21, M20.22
    • An adult with longstanding rheumatoid arthritis is seen for preoperative assessment due to progressive hammertoe formation of the second and third toes causing plantar ulceration and difficulty with ambulation. The deformities are acquired secondary to chronic inflammatory joint destruction and tendon imbalance, and a diagnosis from this group is assigned to document the toe deformities as part of the patients comorbidity profile prior to surgical correction. Typical codes: M20.31, M20.32

    Related Codes

    M21-OTHER-ACQUIRED-DEFORMITIES-OF-LIMBS

    ICD-10-CM Code For Other Acquired Deformities Of Limbs: Group Overview

    M22-DISORDER-OF-PATELLA

    ICD-10-CM Code For Disorder Of Patella: Group Overview

    M23-INTERNAL-DERANGEMENT-OF-KNEE

    ICD-10-CM Code For Internal Derangement Of Knee: Group Overview

    M24-OTHER-SPECIFIC-JOINT-DERANGEMENTS

    ICD-10-CM Code For Other Specific Joint Derangements: Group Overview

    M25-OTHER-JOINT-DISORDER-NOT-ELSEWHERE-CLASSIFIED

    ICD-10-CM Code For Other Joint Disorder Not Elsewhere Classified: Group Overview

    Frequently Asked Questions

    References

    1. 1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
    2. 2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
    3. 3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.
    Published by

    Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

    Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.