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ICD-10 Guide
ICD-10 CodesG56.21

G56.21

Billable

Lesion of ulnar nerve, right upper limb

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

Code Description

ICD-10 G56.21 is a billable code used to indicate a diagnosis of lesion of ulnar nerve, right upper limb.

Key Diagnostic Point:

The ulnar nerve is one of the major nerves of the upper limb, primarily responsible for the sensation and motor function of the hand. A lesion of the ulnar nerve can occur due to various factors, including trauma, compression, or systemic diseases. Clinically, patients may present with symptoms such as numbness, tingling, or weakness in the ring and little fingers, often referred to as 'ulnar nerve palsy.' The condition can arise from entrapment at the elbow (cubital tunnel syndrome) or wrist (Guyon's canal syndrome). Diagnosis typically involves a thorough clinical examination, nerve conduction studies, and electromyography to assess the function of the ulnar nerve and to rule out other neuropathies. Treatment options may include conservative management with splinting and physical therapy or surgical intervention in severe cases. Accurate coding is essential for proper reimbursement and to reflect the complexity of the patient's condition.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Variability in clinical presentation and severity of symptoms
  • Need for detailed documentation of nerve conduction studies
  • Differentiation from other neuropathies and entrapments
  • Potential for co-existing conditions affecting the ulnar nerve

Audit Risk Factors

  • Inadequate documentation of clinical findings
  • Failure to include nerve conduction study results
  • Misidentification of the affected limb
  • Inconsistent coding of co-existing conditions

Specialty Focus

Medical Specialties

Neurology

Documentation Requirements

Detailed neurological examination findings, results of nerve conduction studies, and treatment plans.

Common Clinical Scenarios

Patients presenting with numbness in the ulnar distribution, weakness in hand grip, or symptoms worsening with elbow flexion.

Billing Considerations

Ensure that all diagnostic tests are documented and correlate with the clinical findings.

Orthopedics

Documentation Requirements

Surgical notes, pre-operative assessments, and post-operative follow-ups.

Common Clinical Scenarios

Patients undergoing surgical decompression for cubital tunnel syndrome or ulnar nerve transposition.

Billing Considerations

Document the rationale for surgical intervention and any pre-existing conditions that may affect recovery.

Coding Guidelines

Inclusion Criteria

Use G56.21 When
  • Follow the official ICD
  • CM coding guidelines, ensuring that the code is used only when there is a confirmed diagnosis of ulnar nerve lesion
  • Include any relevant co
  • morbidities and document the specific location of the lesion

Exclusion Criteria

Do NOT use G56.21 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

95900CPT Code

Nerve conduction studies, upper extremity

Clinical Scenario

Used to confirm the diagnosis of ulnar nerve lesions.

Documentation Requirements

Results of the nerve conduction studies must be documented in the patient's medical record.

Specialty Considerations

Neurologists should ensure that the studies are performed according to established protocols.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of ulnar nerve lesions, improving the accuracy of diagnoses and treatment plans. This specificity aids in better tracking of patient outcomes and resource allocation.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of ulnar nerve lesions, improving the accuracy of diagnoses and treatment plans. This specificity aids in better tracking of patient outcomes and resource allocation.

Reimbursement & Billing Impact

The transition to ICD-10 has allowed for more specific coding of ulnar nerve lesions, improving the accuracy of diagnoses and treatment plans. This specificity aids in better tracking of patient outcomes and resource allocation.

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 are the common symptoms of ulnar nerve lesions?

Common symptoms include numbness and tingling in the ring and little fingers, weakness in grip strength, and pain in the elbow or forearm.

How is an ulnar nerve lesion diagnosed?

Diagnosis typically involves a clinical examination, patient history, and nerve conduction studies to assess the function of the ulnar nerve.

What treatments are available for ulnar nerve lesions?

Treatment options may include conservative measures such as splinting and physical therapy, or surgical options like decompression or transposition of the ulnar nerve.