ICD-10-CM Code M20

Acquired deformities of fingers and toes

Version 2020 Non-Billable Code

Not Valid for Submission

M20 is a "header" nonspecific and non-billable code code, consider using a code with a higher level of specificity for a diagnosis of acquired deformities of fingers and toes. The code is NOT valid for the year 2020 for the submission of HIPAA-covered transactions.

ICD-10:M20
Short Description:Acquired deformities of fingers and toes
Long Description:Acquired deformities of fingers and toes

Consider the following ICD-10 codes with a higher level of specificity:

  • 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 - Mallet finger of right finger(s)
  • M20.012 - Mallet finger of left finger(s)
  • M20.019 - Mallet finger of unspecified finger(s)
  • M20.02 - Boutonniere deformity
  • M20.021 - Boutonniere deformity of right finger(s)
  • M20.022 - Boutonniere deformity of left finger(s)
  • M20.029 - Boutonniere deformity of unspecified finger(s)
  • M20.03 - Swan-neck deformity
  • M20.031 - Swan-neck deformity of right finger(s)
  • M20.032 - Swan-neck deformity of left finger(s)
  • M20.039 - Swan-neck deformity 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 finger(s)
  • M20.1 - Hallux valgus (acquired)
  • M20.10 - Hallux valgus (acquired), unspecified foot
  • M20.11 - Hallux valgus (acquired), right foot
  • M20.12 - Hallux valgus (acquired), left foot
  • M20.2 - Hallux rigidus
  • M20.20 - Hallux rigidus, unspecified foot
  • M20.21 - Hallux rigidus, right foot
  • M20.22 - Hallux rigidus, left foot
  • M20.3 - Hallux varus (acquired)
  • M20.30 - Hallux varus (acquired), unspecified foot
  • M20.31 - Hallux varus (acquired), right foot
  • M20.32 - Hallux varus (acquired), left foot
  • M20.4 - Other hammer toe(s) (acquired)
  • M20.40 - Other hammer toe(s) (acquired), unspecified foot
  • M20.41 - Other hammer toe(s) (acquired), right foot
  • M20.42 - Other hammer toe(s) (acquired), 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 foot
  • M20.5X2 - Other deformities of toe(s) (acquired), left foot
  • M20.5X9 - Other deformities of toe(s) (acquired), unspecified foot
  • M20.6 - Acquired deformities of toe(s), unspecified
  • M20.60 - Acquired deformities of toe(s), unspecified, unspecified foot
  • M20.61 - Acquired deformities of toe(s), unspecified, right foot
  • M20.62 - Acquired deformities of toe(s), unspecified, left foot

Tabular List of Diseases and Injuries

The Tabular List of Diseases and Injuries is a list of ICD-10 codes, organized "head to toe" into chapters and sections with guidance for inclusions, exclusions, descriptions and more. The following references are applicable to the code M20:

Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
  • acquired absence of fingers and toes Z89
  • congenital absence of fingers and toes Q71.3 Q72.3
  • congenital deformities and malformations of fingers and toes Q66 Q68 Q70 Q74

Code Classification

  • Diseases of the musculoskeletal system and connective tissue (M00–M99)
    • Other joint disorders (M20-M25)
      • Acquired deformities of fingers and toes (M20)

Code History

  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016
    (First year ICD-10-CM implemented into the HIPAA code set)
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020

Information for Patients


Finger Injuries and Disorders

You use your fingers and thumbs to do everything from grasping objects to playing musical instruments to typing. When there is something wrong with them, it can make life difficult. Common problems include

  • Injuries that result in fractures, ruptured ligaments and dislocations
  • Osteoarthritis - wear-and-tear arthritis. It can also cause deformity.
  • Tendinitis - irritation of the tendons
  • Dupuytren's contracture - a hereditary thickening of the tough tissue that lies just below the skin of your palm. It causes the fingers to stiffen and bend.
  • Trigger finger - an irritation of the sheath that surrounds the flexor tendons. It can cause the tendon to catch and release like a trigger.

[Learn More]