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v1.0.0
ICD-10 Guide
ICD-10 CodesG56.42

G56.42

Billable

Causalgia of left upper limb

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/05/2025

Code Description

ICD-10 G56.42 is a billable code used to indicate a diagnosis of causalgia of left upper limb.

Key Diagnostic Point:

Causalgia, also known as complex regional pain syndrome type II, is a chronic pain condition that typically follows an injury to a peripheral nerve. In the case of G56.42, the condition specifically affects the left upper limb. Patients often experience severe burning pain, allodynia (pain from stimuli that do not normally provoke pain), and hyperalgesia (increased sensitivity to painful stimuli). The pain is often accompanied by changes in skin color, temperature, and swelling in the affected area. The underlying pathophysiology involves a malfunction in the peripheral and central nervous systems, leading to abnormal pain signaling. Diagnosis is primarily clinical, supported by patient history and physical examination, and may involve nerve conduction studies to assess the integrity of the affected nerve. Treatment options include medications, physical therapy, and in some cases, nerve blocks or surgical interventions. Accurate coding is essential for appropriate reimbursement and to reflect the complexity of the condition.

Code Complexity Analysis

Complexity Rating: High

High Complexity

Complexity Factors

  • Requires detailed documentation of symptoms and history.
  • Differentiation from other neuropathic pain conditions.
  • Potential for co-morbid conditions affecting coding.
  • Need for precise anatomical localization of symptoms.

Audit Risk Factors

  • Inadequate documentation of pain severity and duration.
  • Failure to document prior treatments and their outcomes.
  • Misclassification of causalgia as other neuropathic pain syndromes.
  • Lack of supporting diagnostic tests in the medical record.

Specialty Focus

Medical Specialties

Neurology

Documentation Requirements

Detailed neurological examination findings, including sensory and motor assessments.

Common Clinical Scenarios

Patients presenting with chronic pain following a nerve injury or surgery.

Billing Considerations

Documentation should include the impact of symptoms on daily activities and response to previous treatments.

Pain Management

Documentation Requirements

Comprehensive pain assessments, including pain scales and functional impact.

Common Clinical Scenarios

Management of chronic pain with interventional procedures.

Billing Considerations

Documentation of treatment plans and patient consent for procedures is critical.

Coding Guidelines

Inclusion Criteria

Use G56.42 When
  • Follow the official ICD
  • CM guidelines for coding and reporting, ensuring that the diagnosis is supported by clinical documentation
  • Include any relevant history of trauma or surgery that may have led to the causalgia

Exclusion Criteria

Do NOT use G56.42 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

95903CPT Code

Nerve conduction study, each nerve

Clinical Scenario

Used to evaluate the function of the affected nerve in patients with causalgia.

Documentation Requirements

Document the specific nerves tested and the rationale for the study.

Specialty Considerations

Neurologists should ensure comprehensive reports are available for coding.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of causalgia, improving the ability to capture the complexity of the condition and its impact on patient care.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of causalgia, improving the ability to capture the complexity of the condition and its impact on patient care.

Reimbursement & Billing Impact

The transition to ICD-10 has allowed for more specific coding of causalgia, improving the ability to capture the complexity of the condition and its impact on patient care.

Resources

Clinical References

  • •
    ICD-10-CM Official Guidelines for Coding and Reporting

Coding & Billing References

  • •
    ICD-10-CM Official Guidelines for Coding and Reporting

Frequently Asked Questions

What is the difference between causalgia and complex regional pain syndrome?

Causalgia is a type of complex regional pain syndrome that specifically follows a nerve injury, characterized by severe burning pain and other symptoms. Complex regional pain syndrome can occur without a clear nerve injury and may involve more widespread symptoms.