All ICD10 Codes

M21

Non-Billable
ChapterM00–M99
Rankcategory
Official Description

Other acquired deformities of limbs

Use a more specific code (0 billable, 10 non-billable)
M21.0Valgus deformity, not elsewhere classifiedhas subcodesM21.1Varus deformity, not elsewhere classifiedhas subcodesM21.2Flexion deformityhas subcodesM21.3Wrist or foot drop (acquired)has subcodesM21.4Flat foot [pes planus] (acquired)has subcodesM21.5Acquired clawhand, clubhand, clawfoot and clubfoothas subcodesM21.6Other acquired deformities of foothas subcodesM21.7Unequal limb length (acquired)has subcodesM21.8Other specified acquired deformities of limbshas subcodesM21.9Unspecified acquired deformity of limb and handhas subcodes
Metadata & Insights
  • •Non-billable category (requires more specific sub-code).
  • •Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (M00-M99).

CH13 Parent Instructions

Excludes2(Not included here. Code separately if applicable.)
  • 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)

M20-M25 Parent Instructions

Excludes2(Not included here. Code separately if applicable.)

Instructional Notes

Excludes1(Not coded here. Use a different code.)
  • acquired absence of limb (Z89.-)
  • congenital absence of limbs (Q71-Q73)
  • congenital deformities and malformations of limbs (Q65-Q66, Q68-Q74)
Excludes2(Not included here. Code separately if applicable.)
  • acquired deformities of fingers or toes (M20.-)
  • coxa plana (M91.2)

Clinical Hierarchy

BillableHas subcodes
CH13Diseases of the musculoskeletal system and connective tissue (M00-M99)
M20-M25Other joint disorders (M20-M25)
M21Other acquired deformities of limbsNot billable
M21.0Valgus deformity, not elsewhere classifiedSubcodes
M21.1Varus deformity, not elsewhere classifiedSubcodes
M21.2Flexion deformitySubcodes
M21.3Wrist or foot drop (acquired)Subcodes
M21.4Flat foot [pes planus] (acquired)Subcodes
M21.5Acquired clawhand, clubhand, clawfoot and clubfootSubcodes
M21.6Other acquired deformities of footSubcodes
M21.7Unequal limb length (acquired)Subcodes
M21.8Other specified acquired deformities of limbsSubcodes
M21.9Unspecified acquired deformity of limb and handSubcodes

Applicable Ancestor Context

The following parent sections contain instructions or notes that apply to M21:

blockM20-M25
Other joint disorders (M20-M25)
View context instructions
chapterCH13
Diseases of the musculoskeletal system and connective tissue (M00-M99)
View context instructions

MS-DRG Classification

2026

No direct MS-DRG triggers identified.

Cross Reference

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