M21.7
Non-billableUnequal limb length (acquired)
Unequal limb length (acquired)
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 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 (5)
Also Known As / Clinical Terms
Frequently Asked Questions
What is ICD-10 code M21.7?
ICD-10-CM code M21.7 represents "Unequal limb length (acquired)". It is a non-billable header code — use a more specific child code for billing purposes.
Is M21.7 a billable code?
No, M21.7 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 5 child codes under M21.7.
What chapter is M21.7 in?
M21.7 is in Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (codes M00-M99).
What codes cannot be used with M21.7?
M21.7 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 M21.7?
M21.7 has 5 child codes, including: M21.70 (Unequal limb length (acquired), unspecified site), M21.72 (Unequal limb length (acquired), humerus), M21.73 (Unequal limb length (acquired), ulna and radius), M21.75 (Unequal limb length (acquired), femur), and 1 more.
What are the UMLS CUIs for M21.7?
M21.7 is linked to 1 UMLS Concept Unique Identifier: C0494930. 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.