Skip to main content

M20.029 ICD-10-CM Code: Boutonnière deformity of unspecified finger(s)

Billing Status: YES. This is a valid, specific, and billable ICD-10-CM reference.

Inpatient Payment Groups (MS-DRG)

MS-DRGs this diagnosis helps define, as principal or secondary, per the CMS ICD-10-CM/PCS MS-DRG Definitions Manual v43.0, Appendix B.

  • MS-DRG 564 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH MCC (MDC 08)
  • MS-DRG 565 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH CC (MDC 08)
  • MS-DRG 566 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITHOUT CC/MCC (MDC 08)

A diagnosis appearing in a group's logic does not by itself determine the DRG assigned to a stay; the grouper uses the full claim.

Official Registry Overview & Definition

Boutonnière deformity of unspecified finger(s) is a billable ICD-10-CM diagnosis code (M20.029).

Official Tabular Instructional Notes

Sequencing, inclusion, and exclusion notes published for M20.029 in the official ICD-10-CM tabular list.

Excludes1 — Not Coded Here

Conditions generally not reported together with this code (Excludes1) -- an error unless the two conditions are documented as unrelated to each other (ICD-10-CM Official Guidelines, Section I.A.12.a).

Excludes2 — Not Included Here

Conditions not covered by this code, but which may be reported alongside it when both are present.

Frequently Compared Codes

The official Excludes notes on M20.029 name these codes. Each comparison page covers when the two can — or must not — be reported together.

Change history

No changes recorded for this code — unchanged since the FY2016 baseline of the change ledger.

Verify Before Coding

  • No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim.

Relationships & Classification

Other codes that name M20.029 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

1 Excludes1 notes: Z89 (via M20.-).

4 Excludes2 notes: M21 (via M20.-), M24.5 (via M20.-), M25 (via M20.-), M95 (via M20.-).

Potential MS-DRG Relationships (FY2026)

Not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity.

Named in the grouper logic of 3 MS-DRGs: DRG 564 (MDC 08), DRG 565 (MDC 08), DRG 566 (MDC 08).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):MUS023 — Acquired deformities (excluding foot) (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same condition, opposite side

Same category and title, differing only in which side of the body is affected.

M20.021 — Boutonnière deformity of right finger(s) (right)Compare M20.029 vs M20.021 →, M20.022 — Boutonnière deformity of left finger(s) (left)Compare M20.029 vs M20.022 →

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Acquired deformities (excluding foot)).

M20.001 — Unspecified deformity of right finger(s), M20.002 — Unspecified deformity of left finger(s), M20.009 — Unspecified deformity of unspecified finger(s), M20.011 — Mallet finger of right finger(s), M20.012 — Mallet finger of left finger(s), M20.019 — Mallet finger of unspecified finger(s), M20.021 — Boutonnière deformity of right finger(s), M20.022 — Boutonnière deformity of left finger(s), M20.031 — Swan-neck deformity of right finger(s), M20.032 — Swan-neck deformity of left finger(s), M20.039 — Swan-neck deformity of unspecified finger(s), M20.091 — Other deformity of right finger(s), M20.092 — Other deformity of left finger(s), M20.099 — Other deformity of finger(s), unspecified finger(s), M21.00 — Valgus deformity, not elsewhere classified, unspecified site, M21.021 — Valgus deformity, not elsewhere classified, right elbow, M21.022 — Valgus deformity, not elsewhere classified, left elbow, M21.029 — Valgus deformity, not elsewhere classified, unspecified elbow, M21.051 — Valgus deformity, not elsewhere classified, right hip, M21.052 — Valgus deformity, not elsewhere classified, left hip, +124 more

Contextual Map

Every relationship of M20.029 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Hierarchy

  • M00-M99 — Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (M00-M99) (M00-M99) [Hierarchy]
  • M00-M25 — Arthropathies [Hierarchy]
  • M20-M25 — Other joint disorders [Hierarchy]

Referenced by Excludes1 notes

  • Z89 — Acquired absence of limb [Excludes1](via M20.-): “acquired deformities of limbs (M20-M21)” · check together

Referenced by Excludes2 notes

  • M21 — Other acquired deformities of limbs [Excludes2](via M20.-): “acquired deformities of fingers or toes (M20.-)” · check together
  • M24.5 — Contracture of joint [Excludes2](via M20.-): “acquired deformities of limbs (M20-M21)” · check together
  • M25 — Other joint disorder, not elsewhere classified [Excludes2](via M20.-): “acquired deformities of limb (M20-M21)” · check together
  • M95 — Other acquired deformities of musculoskeletal system and connective tissue [Excludes2](via M20.-): “acquired deformities of limbs (M20-M21)” · check together

Clinical classification (CCSR)

  • MUS023 — Acquired deformities (excluding foot) [CCSR]

Potential MS-DRG

  • DRG 564 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH MCC [MS-DRG]: “OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH MCC (MDC 08)”
  • DRG 565 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH CC [MS-DRG]: “OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITH CC (MDC 08)”
  • DRG 566 — OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITHOUT CC/MCC [MS-DRG]: “OTHER MUSCULOSKELETAL SYSTEM AND CONNECTIVE TISSUE DIAGNOSES WITHOUT CC/MCC (MDC 08)”

MDC crossing · procedures (18508)

  • MDC 08 — Diseases and Disorders of the Musculoskeletal System and Connective Tissue [MDC crossing]: “Diseases and Disorders of the Musculoskeletal System and Connective Tissue — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”
  • 005T0ZZ — Destruction of Spinal Meninges, Open Approach [Same-MDC procedure]: “Destruction of Spinal Meninges, Open Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
  • 005T3ZZ — Destruction of Spinal Meninges, Percutaneous Approach [Same-MDC procedure]: “Destruction of Spinal Meninges, Percutaneous Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
  • 005T4ZZ — Destruction of Spinal Meninges, Percutaneous Endoscopic Approach [Same-MDC procedure]: “Destruction of Spinal Meninges, Percutaneous Endoscopic Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
  • 005W0Z3 — Destruction of Cervical Spinal Cord using Laser Interstitial Thermal Therapy, Open Approach [Same-MDC procedure]: “Destruction of Cervical Spinal Cord using Laser Interstitial Thermal Therapy, Open Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
  • 005W0ZZ — Destruction of Cervical Spinal Cord, Open Approach [Same-MDC procedure]: “Destruction of Cervical Spinal Cord, Open Approach — grouped in MDC 08, the procedure side of this code's crossing.” · check together
  • and 18503 more

Nearest codes (40)

  • M20 — Acquired deformities of fingers and toes [Sibling]
  • M20.0 — Deformity of finger(s) [Sibling]
  • M20.00 — Unspecified deformity of finger(s) [Sibling]
  • M20.001 — Unspecified deformity of right finger(s) [Sibling]
  • M20.002 — Unspecified deformity of left finger(s) [Sibling]
  • M20.009 — Unspecified deformity of unspecified finger(s) [Sibling]
  • M20.01 — Mallet finger [Sibling]
  • M20.011 — Mallet finger of right finger(s) [Sibling]
  • and 32 more

Nearest Codes in This Family

Official ICD-10-CM classifications closest to M20.029 in its code family, with their registry titles.

  • M20.012 — Mallet finger of left finger(s)
  • M20.019 — Mallet finger of unspecified finger(s)
  • M20.02 — Boutonnière deformity
  • M20.021 — Boutonnière deformity of right finger(s)
  • M20.022 — Boutonnière deformity of left finger(s)
  • M20.03 — Swan-neck deformity
  • M20.031 — Swan-neck deformity of right finger(s)
  • M20.032 — Swan-neck deformity of left finger(s)
  • M20.039 — Swan-neck deformity of unspecified finger(s)
  • M20.09 — Other deformity of finger(s)

View all codes in the M20 family