ICD-10-CM 2027 diagnosis code

G56Mononeuropathies of upper limb

Not billable — use a more specific code

G56 is a header code, so it can't be reported by itself. Choose one of the 7 more specific codes beneath it.

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 G56

G56 is the ICD-10-CM diagnosis code for mononeuropathies of upper limb. It belongs to block G50-G59 (nerve, nerve root and plexus disorders) and chapter 6 (diseases of the nervous system). It is a header code, so it can't be reported by itself; one of its 7 subcodes must be used instead.

To report this condition, pick the subcode that matches the documentation: G56.0 (syndrome), G56.1 (nerve), G56.2 (nerve), G56.3 (nerve), G56.4 (limb), G56.8 (limb) and G56.9 (limb).

Don't report G56 together with the conditions in its Excludes1 note: current traumatic nerve disorder - see nerve injury by body region.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Specific codes under G56

Coding notes

Excludes1Not coded here — never report together with this code

current traumatic nerve disorder - see nerve injury by body region

Notes that apply from higher levels

Instructions written at a parent level also apply to G56.

Broader instructions also apply from G50-G59 Nerve, nerve root and plexus disorders and Chapter 6: Diseases of the nervous system.

Codes whose notes reference G56

M79.2Excludes1

Code history

2016
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2021
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2023
2024
2025
2026
2027

FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
No changes since FY2016.

Common questions about G56

Is G56 billable?: No. G56 is a header code. Report one of its more specific subcodes instead.