ICD-10-CM 2027 diagnosis code
S56.4Injury of extensor muscle, fascia and tendon of other and unspecified finger at forearm level
S56.4 is a header code, so it can't be reported by itself. Choose one of the 4 more specific codes beneath it and add the required 7th character.Short description: Inj extensor musc/fasc/tend and unsp finger at forarm lv
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About S56.4
S56.4 is the ICD-10-CM diagnosis code for injury of extensor muscle, fascia and tendon of other and unspecified finger at forearm level. It belongs to category S56 (injury of muscle, fascia and tendon at forearm level), block S50-S59 (injuries to the elbow and forearm) and chapter 19 (injury, poisoning and certain other consequences of external causes). It is a header code, so it can't be reported by itself; one of its 4 subcodes must be used instead.
Within S56, choose S56.4 (extensor muscle, fascia and tendon of other and unspecified finger at forearm level) only when documentation doesn't support a more specific option: flexor muscle, fascia and tendon of thumb at forearm level (S56.0), flexor muscle, fascia and tendon of other and unspecified finger at forearm level (S56.1), other flexor muscle, fascia and tendon at forearm level (S56.2), extensor or abductor muscles, fascia and tendons of thumb at forearm level (S56.3), other extensor muscle, fascia and tendon at forearm level (S56.5), other muscles, fascia and tendons at forearm level (S56.8) and unspecified muscles, fascia and tendons at forearm level (S56.9).
Codes in this range require a 7th character: A for initial encounter, D for subsequent encounter and S for sequela. Use placeholder "X" characters to fill any empty positions before the 7th character.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
7th character
The appropriate 7th character is to be added to each code from category S56
- S56.40Unspecified injury of extensor muscle, fascia and tendon of other and unspecified finger at forearm level
- S56.401Unspecified injury of extensor muscle, fascia and tendon of right index finger at forearm level
- S56.402Unspecified injury of extensor muscle, fascia and tendon of left index finger at forearm level
- S56.403Unspecified injury of extensor muscle, fascia and tendon of right middle finger at forearm level
- S56.404Unspecified injury of extensor muscle, fascia and tendon of left middle finger at forearm level
- S56.405Unspecified injury of extensor muscle, fascia and tendon of right ring finger at forearm level
- S56.406Unspecified injury of extensor muscle, fascia and tendon of left ring finger at forearm level
- S56.407Unspecified injury of extensor muscle, fascia and tendon of right little finger at forearm level
- S56.408Unspecified injury of extensor muscle, fascia and tendon of left little finger at forearm level
- S56.409Unspecified injury of extensor muscle, fascia and tendon of unspecified finger at forearm level
- S56.41Strain of extensor muscle, fascia and tendon of other and unspecified finger at forearm level
- S56.411Strain of extensor muscle, fascia and tendon of right index finger at forearm level
- S56.412Strain of extensor muscle, fascia and tendon of left index finger at forearm level
- S56.413Strain of extensor muscle, fascia and tendon of right middle finger at forearm level
- S56.414Strain of extensor muscle, fascia and tendon of left middle finger at forearm level
- S56.415Strain of extensor muscle, fascia and tendon of right ring finger at forearm level
- S56.416Strain of extensor muscle, fascia and tendon of left ring finger at forearm level
- S56.417Strain of extensor muscle, fascia and tendon of right little finger at forearm level
- S56.418Strain of extensor muscle, fascia and tendon of left little finger at forearm level
- S56.419Strain of extensor muscle, fascia and tendon of finger, unspecified finger at forearm level
- S56.42Laceration of extensor muscle, fascia and tendon of other and unspecified finger at forearm level
- S56.421Laceration of extensor muscle, fascia and tendon of right index finger at forearm level
- S56.422Laceration of extensor muscle, fascia and tendon of left index finger at forearm level
- S56.423Laceration of extensor muscle, fascia and tendon of right middle finger at forearm level
- S56.424Laceration of extensor muscle, fascia and tendon of left middle finger at forearm level
- S56.425Laceration of extensor muscle, fascia and tendon of right ring finger at forearm level
- S56.426Laceration of extensor muscle, fascia and tendon of left ring finger at forearm level
- S56.427Laceration of extensor muscle, fascia and tendon of right little finger at forearm level
- S56.428Laceration of extensor muscle, fascia and tendon of left little finger at forearm level
- S56.429Laceration of extensor muscle, fascia and tendon of unspecified finger at forearm level
- S56.49Other injury of extensor muscle, fascia and tendon of other and unspecified finger at forearm level
- S56.491Other injury of extensor muscle, fascia and tendon of right index finger at forearm level
- S56.492Other injury of extensor muscle, fascia and tendon of left index finger at forearm level
- S56.493Other injury of extensor muscle, fascia and tendon of right middle finger at forearm level
- S56.494Other injury of extensor muscle, fascia and tendon of left middle finger at forearm level
- S56.495Other injury of extensor muscle, fascia and tendon of right ring finger at forearm level
- S56.496Other injury of extensor muscle, fascia and tendon of left ring finger at forearm level
- S56.497Other injury of extensor muscle, fascia and tendon of right little finger at forearm level
- S56.498Other injury of extensor muscle, fascia and tendon of left little finger at forearm level
- S56.499Other injury of extensor muscle, fascia and tendon of unspecified finger at forearm level
- Ainitial encounter
- Dsubsequent encounter
- Ssequela
Notes that apply from higher levels
Instructions written at a parent level also apply to S56.4.
Broader instructions also apply from S50-S59 Injuries to the elbow and forearm and Chapter 19: Injury, poisoning and certain other consequences of external causes.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about S56.4
Is S56.4 billable?
- No. S56.4 is a header code. Report one of its more specific subcodes instead.