M21.70
BillableUnequal limb length (acquired), unspecified site
Unequal limb length (acquired), unspecified site
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
Related Codes(4)
Also Known As / Clinical Terms(35)
SNOMED CT
- Piston sign57756003
- Telescoping of limb at hip57756003
- Acquired unequal arm length203602007
- Acquired unequal upper limb length203602007
- Short arm249739008
- Proximal shortening of arm249740005
- Shortening of middle section of arm249741009
- Distal shortening of arm249742002
- Short leg249786007
- Apparent shortening of leg249787003
- Functional shortening of leg249787003
- Structural shortening of leg249788008
- True shortening of leg249788008
- Proximal shortening of leg249790009
- Shortening of middle section of leg249791008
- Distal shortening of leg249792001
- Acquired unequal limb length300261000119100
Clinical Terms
- Piston sign
- Proximal shortening of arm
- Short leg
- Shortening of middle section of arm
- Functional shortening of leg
- Proximal shortening of leg
- Acquired unequal limb length
- Apparent shortening of leg
- Short arm
- Shortening of middle section of leg
- Structural shortening of leg
- Telescoping of limb at hip
- Distal shortening of leg
- Acquired unequal upper limb length
- Acquired unequal arm length
- Distal shortening of arm
- True shortening of leg
Frequently Asked Questions
What is the ICD-10 code for unequal limb length (acquired), unspecified site?
The ICD-10-CM code for unequal limb length (acquired), unspecified site is M21.70. The full clinical description is "Unequal limb length (acquired), unspecified site". M21.70 is a billable/specific code that can be used on insurance claims and medical billing.
What does ICD-10 code M21.70 mean?
ICD-10-CM code M21.70 represents “Unequal limb length (acquired), unspecified site”. It is classified under Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue and is a billable/specific code that can be used on a claim.
Is M21.70 a billable code?
Yes, M21.70 is a billable/specific ICD-10-CM code and can be used to indicate a diagnosis on a medical claim.
What chapter is M21.70 in?
M21.70 is in Chapter 13: Diseases of the Musculoskeletal System and Connective Tissue (codes M00-M99).
What codes cannot be used with M21.70?
M21.70 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 SNOMED CT codes does M21.70 map to?
M21.70 maps to 13 SNOMED CT concepts: 203602007, 300261000119100, 249787003, 249742002, 249792001, and 8 more. SNOMED CT is a clinical terminology used in electronic health records.
What are the UMLS CUIs for M21.70?
M21.70 is linked to 1 UMLS Concept Unique Identifier: C0838042. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does M21.70 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like unequal limb length (acquired), unspecified site 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 M21.70?
There is no direct ICD-11 mapping available for M21.70 in the WHO crosswalk tables. This may mean the concept is classified differently in ICD-11. Use the ICD-10 to ICD-11 converter to search for related codes.
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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.