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M21

Non-billable

Other acquired deformities of limbs

Other acquired deformities of limbs

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

Child Codes

10

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)

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 (10)

M21.0

Valgus deformity, not elsewhere classified

M21.1

Varus deformity, not elsewhere classified

M21.2

Flexion deformity

M21.3

Wrist or foot drop (acquired)

M21.4

Flat foot [pes planus] (acquired)

M21.5

Acquired clawhand, clubhand, clawfoot and clubfoot

M21.6

Other acquired deformities of foot

M21.7

Unequal limb length (acquired)

M21.8

Other specified acquired deformities of limbs

M21.9

Unspecified acquired deformity of limb and hand

Also Known As / Clinical Terms

UMLS

Frequently Asked Questions

What is ICD-10 code M21?

ICD-10-CM code M21 represents "Other acquired deformities of limbs". It is a non-billable header code — use a more specific child code for billing purposes.

Is M21 a billable code?

No, M21 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 10 child codes under M21.

What chapter is M21 in?

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

What codes cannot be used with M21?

M21 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).

What are the subcategories under M21?

M21 has 10 child codes, including: M21.0 (Valgus deformity, not elsewhere classified), M21.1 (Varus deformity, not elsewhere classified), M21.2 (Flexion deformity), M21.3 (Wrist or foot drop (acquired)), and 6 more.

What are the UMLS CUIs for M21?

M21 is linked to 1 UMLS Concept Unique Identifier: C0158463. 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.