2020 ICD-10-CM Diagnosis Code M21.179

Varus deformity, not elsewhere classified, unspecified ankle

    2016 2017 2018 2019 2020 Billable/Specific Code
  • M21.179 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2020 edition of ICD-10-CM M21.179 became effective on October 1, 2019.
  • This is the American ICD-10-CM version of M21.179 - other international versions of ICD-10 M21.179 may differ.
The following code(s) above M21.179 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to M21.179:
  • M00-M99
    2020 ICD-10-CM Range M00-M99

    Diseases of the musculoskeletal system and connective tissue

    Note
    • Use an external cause code following the code for the musculoskeletal condition, if applicable, to identify the cause of the musculoskeletal condition
    Type 2 Excludes
    • 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)
    Diseases of the musculoskeletal system and connective tissue
  • M20-M25
    2020 ICD-10-CM Range M20-M25

    Other joint disorders

    Type 2 Excludes
    Other joint disorders
  • M21
    ICD-10-CM Diagnosis Code M21

    Other acquired deformities of limbs

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • acquired absence of limb (Z89.-)
    • congenital absence of limbs (Q71-Q73)
    • congenital deformities and malformations of limbs (Q65-Q66, Q68-Q74)
    Type 2 Excludes
    • acquired deformities of fingers or toes (M20.-)
    • coxa plana (M91.2)
    Other acquired deformities of limbs
  • M21.1
    ICD-10-CM Diagnosis Code M21.1

    Varus deformity, not elsewhere classified

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Type 1 Excludes
    Varus deformity, not elsewhere classified
Approximate Synonyms
  • Acquired varus deformity of ankle
  • Varus deformity of ankle
ICD-10-CM M21.179 is grouped within Diagnostic Related Group(s) (MS-DRG v37.0):
  • 564 Other musculoskeletal system and connective tissue diagnoses with mcc
  • 565 Other musculoskeletal system and connective tissue diagnoses with cc
  • 566 Other musculoskeletal system and connective tissue diagnoses without cc/mcc

Convert M21.179 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change
ICD-10-CM Codes Adjacent To M21.179
M21.151 Varus deformity, not elsewhere classified, right hip
M21.152 Varus deformity, not elsewhere classified, left hip
M21.159 Varus deformity, not elsewhere classified, unspecified
M21.16 Varus deformity, not elsewhere classified, knee
M21.161 Varus deformity, not elsewhere classified, right knee
M21.162 Varus deformity, not elsewhere classified, left knee
M21.169 Varus deformity, not elsewhere classified, unspecified knee
M21.17 Varus deformity, not elsewhere classified, ankle
M21.171 Varus deformity, not elsewhere classified, right ankle
M21.172 Varus deformity, not elsewhere classified, left ankle
M21.179 Varus deformity, not elsewhere classified, unspecified ankle
M21.2 Flexion deformity
M21.20 …… unspecified site
M21.21 Flexion deformity, shoulder
M21.211 Flexion deformity, right shoulder
M21.212 Flexion deformity, left shoulder
M21.219 Flexion deformity, unspecified shoulder
M21.22 Flexion deformity, elbow
M21.221 Flexion deformity, right elbow
M21.222 Flexion deformity, left elbow
M21.229 Flexion deformity, unspecified elbow

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.