M21.9
Non-billableUnspecified acquired deformity of limb and hand
Unspecified acquired deformity of limb and hand
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Excludes 1
Codes that cannot be used together with this code (mutual exclusion)
Excludes 2
Conditions not included here, but the patient may have both
- •arthropathic psoriasisL40.5
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •compartment syndrome (traumatic)A-)T79
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations, and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
- •joints of the spineM40-M54
- •acquired deformities of fingers or toesM20
- •coxa planaM91.2
Child Codes (6)
Related Codes(9)
M21.0Valgus deformity, not elsewhere classified
M21.1Varus deformity, not elsewhere classified
M21.2Flexion deformity
M21.3Wrist or foot drop (acquired)
M21.4Flat foot [pes planus] (acquired)
M21.5Acquired clawhand, clubhand, clawfoot and clubfoot
M21.6Other acquired deformities of foot
M21.7Unequal limb length (acquired)
M21.8Other specified acquired deformities of limbs
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(1)
Frequently Asked Questions
What is the ICD-10 code for unspecified acquired deformity of limb and hand?
The ICD-10-CM code for unspecified acquired deformity of limb and hand is M21.9. The full clinical description is "Unspecified acquired deformity of limb and hand". M21.9 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code M21.9 mean?
ICD-10-CM code M21.9 represents “Unspecified acquired deformity of limb and hand”. It is classified under Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue and is a non-billable header code. Use a more specific child code for billing purposes.
Is M21.9 a billable code?
No, M21.9 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 6 child codes under M21.9.
What chapter is M21.9 in?
M21.9 is in Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (codes M00-M99).
What codes cannot be used with M21.9?
M21.9 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 M21.9?
M21.9 has 6 child codes, including: M21.90 (Unspecified acquired deformity of unspecified limb), M21.92 (Unspecified acquired deformity of upper arm), M21.93 (Unspecified acquired deformity of forearm), M21.94 (Unspecified acquired deformity of hand), and 2 more.
What are the UMLS CUIs for M21.9?
M21.9 is linked to 1 UMLS Concept Unique Identifier: C0838057. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does M21.9 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like unspecified acquired deformity of limb and hand affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of M21.9?
M21.9 maps to the ICD-11 code: FA31.Z (Acquired deformities of limbs, unspecified).
Automate ICD-10 Coding With AI
Send clinical text to the AutoICD API and get back structured ICD-10 codes with confidence scores. Integrates into any EHR or billing system in minutes.
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.