AutoICD API

M21.4

Non-billable

Flat foot [pes planus] (acquired)

Flat foot [pes planus] (acquired)

This is a header/category code. For billing purposes, use a more specific child code from the list below.

Status

Non-billable / Header

Block

M20-M25

Parent Code

M21

Child Codes

3

Coding Notes

Excludes 1

Codes that cannot be used together with this code (mutual exclusion)

  • acquired absence of limb (Z89.-)
  • congenital absence of limbs (Q71-Q73)
  • congenital deformities and malformations of limbs (Q65-Q66, Q68-Q74)
  • congenital pes planus (Q66.5-)

Excludes 2

Conditions not included here, but the patient may have both

  • arthropathic psoriasis (L40.5-)
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • compartment syndrome (traumatic) (T79.A-)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations, and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
  • joints of the spine (M40-M54)
  • acquired deformities of fingers or toes (M20.-)
  • coxa plana (M91.2)

Child Codes (3)

M21.40

Flat foot [pes planus] (acquired), unspecified foot

BillableM21.41

Flat foot [pes planus] (acquired), right foot

BillableM21.42

Flat foot [pes planus] (acquired), left foot

Billable

Also Known As / Clinical Terms

UMLS

Frequently Asked Questions

What is ICD-10 code M21.4?

ICD-10-CM code M21.4 represents "Flat foot [pes planus] (acquired)". It is a non-billable header code — use a more specific child code for billing purposes.

Is M21.4 a billable code?

No, M21.4 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 3 child codes under M21.4.

What chapter is M21.4 in?

M21.4 is in Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (codes M00-M99).

What codes cannot be used with M21.4?

M21.4 has Excludes1 notes indicating codes that cannot be used together with it, including: acquired absence of limb (Z89.-); congenital absence of limbs (Q71-Q73); congenital deformities and malformations of limbs (Q65-Q66, Q68-Q74); and 1 more.

What are the subcategories under M21.4?

M21.4 has 3 child codes, including: M21.40 (Flat foot [pes planus] (acquired), unspecified foot), M21.41 (Flat foot [pes planus] (acquired), right foot), M21.42 (Flat foot [pes planus] (acquired), left foot).

What are the UMLS CUIs for M21.4?

M21.4 is linked to 1 UMLS Concept Unique Identifier: C0264133. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.

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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.