2017/18 ICD-10-CM Diagnosis Code M21

Other acquired deformities of limbs

Type 1 Excludes
Type 1 Excludes Help
A type 1 excludes note is a pure excludes. It means "not coded here". A type 1 excludes note indicates that the code excluded should never be used at the same time as M21. A type 1 excludes note is for used for when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • acquired absence of limb (
    ICD-10-CM Diagnosis Code Z89
    • Z89 Acquired absence of limb
      • Z89.0 Acquired absence of thumb and other finger(s)...
        • Z89.01 Acquired absence of thumb
          • Z89.011 Acquired absence of right thumb
          • Z89.012 Acquired absence of left thumb
          • Z89.019 Acquired absence of unspecified thumb
        • Z89.02 Acquired absence of other finger(s)
          • Z89.021 Acquired absence of right finger(s)
          • Z89.022 Acquired absence of left finger(s)
          • Z89.029 Acquired absence of unspecified finger(s)
      • Z89.1 Acquired absence of hand and wrist
        • Z89.11 Acquired absence of hand
          • Z89.111 Acquired absence of right hand
          • Z89.112 Acquired absence of left hand
          • Z89.119 Acquired absence of unspecified hand
        • Z89.12 Acquired absence of wrist
          • Z89.121 Acquired absence of right wrist
          • Z89.122 Acquired absence of left wrist
          • Z89.129 Acquired absence of unspecified wrist
      • Z89.2 Acquired absence of upper limb above wrist
        • Z89.20 Acquired absence of upper limb, unspecified l...
          • Z89.201 Acquired absence of right upper limb, unspeci...
          • Z89.202 Acquired absence of left upper limb, unspecif...
          • Z89.209 Acquired absence of unspecified upper limb, u...
        • Z89.21 Acquired absence of upper limb below elbow
          • Z89.211 Acquired absence of right upper limb below el...
          • Z89.212 Acquired absence of left upper limb below elb...
          • Z89.219 Acquired absence of unspecified upper limb be...
        • Z89.22 Acquired absence of upper limb above elbow
          • Z89.221 Acquired absence of right upper limb above el...
          • Z89.222 Acquired absence of left upper limb above elb...
          • Z89.229 Acquired absence of unspecified upper limb ab...
        • Z89.23 Acquired absence of shoulder
          • Z89.231 Acquired absence of right shoulder
          • Z89.232 Acquired absence of left shoulder
          • Z89.239 Acquired absence of unspecified shoulder
      • Z89.4 Acquired absence of toe(s), foot, and ankle
        • Z89.41 Acquired absence of great toe
          • Z89.411 Acquired absence of right great toe
          • Z89.412 Acquired absence of left great toe
          • Z89.419 Acquired absence of unspecified great toe
        • Z89.42 Acquired absence of other toe(s)
          • Z89.421 Acquired absence of other right toe(s)
          • Z89.422 Acquired absence of other left toe(s)
          • Z89.429 Acquired absence of other toe(s), unspecified...
        • Z89.43 Acquired absence of foot
          • Z89.431 Acquired absence of right foot
          • Z89.432 Acquired absence of left foot
          • Z89.439 Acquired absence of unspecified foot
        • Z89.44 Acquired absence of ankle
          • Z89.441 Acquired absence of right ankle
          • Z89.442 Acquired absence of left ankle
          • Z89.449 Acquired absence of unspecified ankle
      • Z89.5 Acquired absence of leg below knee
        • Z89.51 Acquired absence of leg below knee
          • Z89.511 Acquired absence of right leg below knee
          • Z89.512 Acquired absence of left leg below knee
          • Z89.519 Acquired absence of unspecified leg below kne...
        • Z89.52 Acquired absence of knee
          • Z89.521 Acquired absence of right knee
          • Z89.522 Acquired absence of left knee
          • Z89.529 Acquired absence of unspecified knee
      • Z89.6 Acquired absence of leg above knee
        • Z89.61 Acquired absence of leg above knee
          • Z89.611 Acquired absence of right leg above knee
          • Z89.612 Acquired absence of left leg above knee
          • Z89.619 Acquired absence of unspecified leg above kne...
        • Z89.62 Acquired absence of hip
          • Z89.621 Acquired absence of right hip joint
          • Z89.622 Acquired absence of left hip joint
          • Z89.629 Acquired absence of unspecified hip joint
      • Z89.9 Acquired absence of limb, unspecified
    Z89.-
    )
  • congenital absence of limbs (
    ICD-10-CM Diagnosis Code Q71

    Reduction defects of upper limb

      2016 2017 2018 Non-Billable/Non-Specific Code
    Q71
    -
    ICD-10-CM Diagnosis Code Q73

    Reduction defects of unspecified limb

      2016 2017 2018 Non-Billable/Non-Specific Code
    Q73
    )
  • congenital deformities and malformations of limbs (
    ICD-10-CM Diagnosis Code Q65

    Congenital deformities of hip

      2016 2017 2018 Non-Billable/Non-Specific Code
    Type 1 Excludes
    Q65
    -
    ICD-10-CM Diagnosis Code Q66

    Congenital deformities of feet

      2016 2017 2018 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • reduction defects of feet (Q72.-)
    • valgus deformities (acquired) (M21.0-)
    • varus deformities (acquired) (M21.1-)
    Q66
    ,
    ICD-10-CM Diagnosis Code Q68

    Other congenital musculoskeletal deformities

      2016 2017 2018 Non-Billable/Non-Specific Code
    Type 1 Excludes
    • reduction defects of limb(s) (Q71-Q73)
    Type 2 Excludes
    • congenital myotonic chondrodystrophy (G71.13)
    Q68
    -
    ICD-10-CM Diagnosis Code Q74

    Other congenital malformations of limb(s)

      2016 2017 2018 Non-Billable/Non-Specific Code
    Type 1 Excludes
    Q74
    )
Type 2 Excludes
Type 2 Excludes Help
A type 2 excludes note represents "not included here". A type 2 excludes note indicates that the condition excluded is not part of the condition it is excluded from but a patient may have both conditions at the same time. When a type 2 excludes note appears under a code it is acceptable to use both the code (M21) and the excluded code together.
  • acquired deformities of fingers or toes (
    ICD-10-CM Diagnosis Code M20
    • M20 Acquired deformities of fingers and toes
      • M20.0 Deformity of finger(s)
        • M20.00 Unspecified deformity of finger(s)
          • M20.001 Unspecified deformity of right finger(s)
          • M20.002 Unspecified deformity of left finger(s)
          • M20.009 Unspecified deformity of unspecified finger(s...
        • M20.01 Mallet finger
          • M20.011 …… of right finger(s)
          • M20.012 …… of left finger(s)
          • M20.019 …… of unspecified finger(s)
        • M20.02 Boutonnière deformity
          • M20.021 …… of right finger(s)
          • M20.022 …… of left finger(s)
          • M20.029 Boutonnière deformity of unspecified finger(s...
        • M20.03 Swan-neck deformity
          • M20.031 …… of right finger(s)
          • M20.032 …… of left finger(s)
          • M20.039 …… of unspecified finger(s)
        • M20.09 Other deformity of finger(s)
          • M20.091 Other deformity of right finger(s)
          • M20.092 Other deformity of left finger(s)
          • M20.099 Other deformity of finger(s), unspecified fin...
      • M20.1 Hallux valgus (acquired)
      • M20.2 Hallux rigidus
      • M20.3 Hallux varus (acquired)
      • M20.4 Other hammer toe(s) (acquired)
        • M20.40 Other hammer toe(s) (acquired), unspecified f...
        • M20.41 …… right foot
        • M20.42 …… left foot
      • M20.5 Other deformities of toe(s) (acquired)
        • M20.5X Other deformities of toe(s) (acquired)
          • M20.5X1 Other deformities of toe(s) (acquired), right...
          • M20.5X2 Other deformities of toe(s) (acquired), left ...
          • M20.5X9 Other deformities of toe(s) (acquired), unspe...
      • M20.6 Acquired deformities of toe(s), unspecified
        • M20.60 Acquired deformities of toe(s), unspecified, ...
        • M20.61 Acquired deformities of toe(s), unspecified, ...
        • M20.62 Acquired deformities of toe(s), unspecified, ...
    M20.-
    )
  • coxa plana (
    ICD-10-CM Diagnosis Code M91.2

    Coxa plana

      2016 2017 2018 Non-Billable/Non-Specific Code
    Applicable To
    • Hip deformity due to previous juvenile osteochondrosis
    M91.2
    )
The following code(s) above M21 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:
  • M00-M99
    2018 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
    2018 ICD-10-CM Range M20-M25

    Other joint disorders

    Type 2 Excludes
    Other joint disorders
Code History
Code annotations containing back-references to M21:
ICD-10-CM Codes Adjacent To M21
M20.42 …… left foot
M20.5 Other deformities of toe(s) (acquired)
M20.5X Other deformities of toe(s) (acquired)
M20.5X1 …… right foot
M20.5X2 …… left foot
M20.5X9 …… unspecified foot
M20.6 Acquired deformities of toe(s), unspecified
M20.60 …… unspecified foot
M20.61 …… right foot
M20.62 …… left foot
M21 Other acquired deformities of limbs
M21.0 Valgus deformity, not elsewhere classified
M21.00 …… unspecified site
M21.02 Valgus deformity, not elsewhere classified, elbow
M21.021 Valgus deformity, not elsewhere classified, right elbow
M21.022 Valgus deformity, not elsewhere classified, left elbow
M21.029 Valgus deformity, not elsewhere classified, unspecified elbow
M21.05 Valgus deformity, not elsewhere classified, hip
M21.051 Valgus deformity, not elsewhere classified, right hip
M21.052 Valgus deformity, not elsewhere classified, left hip
M21.059 Valgus deformity, not elsewhere classified, unspecified hip

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