HealthAssure
HealthAssureGood Life
ICD10BillableValid for clinical use

ICD-10 Code G56.40: Causalgia of unspecified upper limb

G56.40 is a billable ICD-10 diagnosis code used to classify Causalgia of unspecified upper limb in medical records and claims. You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records. ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).

What is this code?

ICD-10 codes are diagnosis classification codes used in healthcare records, reporting, coding workflows, and billing support. This code sits within the broader ICD-10 area for Diseases of the nervous system (G00-G99).

When is it used?

  • May be used when a clinician documents causalgia of unspecified upper limb in a patient's medical record.
  • May appear in hospital records, claims, referrals, and clinical documentation.
  • This code can be used as a clinically usable diagnosis entry in standardized coding workflows.

What it does not mean

  • A code alone does not explain severity, treatment plan, or outcome.
  • A medical code should not be treated as a substitute for a doctor's diagnosis or advice.

Code hierarchy

chapter
6Diseases of the nervous system (G00-G99)
block
G50-G59Nerve, nerve root and plexus disorders
category
G56Mononeuropathies of upper limb
category
G56.4Causalgia of upper limb
currentG56.4

Where you may see this code

You may see this code in hospital records, discharge summaries, insurance claims, encounter documentation, referrals, or other healthcare billing and coding records.

Related specialists

NeurologistGeneral Physician

Coverage-related procedures and services

CPT 64416high
INJECTION(S), ANESTHETIC AGENT(S) AND/OR STEROID; BRACHIAL PLEXUS, CONTINUOUS INFUSION BY CATHETER (INCLUDING CATHETER PLACEMENT), INCLUDING IMAGING GUIDANCE, WHEN PERFORMED
Source: CMS coverage guidance
CPT 64448high
INJECTION(S), ANESTHETIC AGENT(S) AND/OR STEROID; FEMORAL NERVE, CONTINUOUS INFUSION BY CATHETER (INCLUDING CATHETER PLACEMENT), INCLUDING IMAGING GUIDANCE, WHEN PERFORMED
Source: CMS coverage guidance
CPT 64449high
INJECTION(S), ANESTHETIC AGENT(S) AND/OR STEROID; LUMBAR PLEXUS, POSTERIOR APPROACH, CONTINUOUS INFUSION BY CATHETER (INCLUDING CATHETER PLACEMENT)
Source: CMS coverage guidance
CPT 64446high
INJECTION(S), ANESTHETIC AGENT(S) AND/OR STEROID; SCIATIC NERVE, CONTINUOUS INFUSION BY CATHETER (INCLUDING CATHETER PLACEMENT), INCLUDING IMAGING GUIDANCE, WHEN PERFORMED
Source: CMS coverage guidance
CPT 72126high
COMPUTED TOMOGRAPHY, CERVICAL SPINE; WITH CONTRAST MATERIAL
Source: CMS coverage guidance
CPT 72125high
COMPUTED TOMOGRAPHY, CERVICAL SPINE; WITHOUT CONTRAST MATERIAL
Source: CMS coverage guidance

Coding guidelines

Common synonyms

Causalgia of unspecified upper limbCausalgia of upper limb

Frequently asked questions

Code details

CodeG56.40
SystemICD10
Display nameCausalgia of unspecified upper limb
ChapterDiseases of the nervous system (G00-G99)
BlockNerve, nerve root and plexus disorders

Flags

BillableYes
Valid clinical useYes

Source

SourceICD-10
Version2026-annual
Releaseannual
Year2026

About this content

This page is prepared by HealthAssure's clinical team using official coding standards from ICD-10. AI tools assist with drafting explanations, which are then reviewed and verified by healthcare professionals for accuracy. This content is for informational purposes and does not replace professional medical advice. Meet our team.