ICD-10 for Left Ankle Pain: Complete Coding Guide

The ICD-10 for left ankle pain is M25.572. This code applies when pain is documented in the left ankle or joints of the left foot, and no specific underlying condition is confirmed. It is a symptom code, often used temporarily until further evaluation identifies the exact diagnosis.

Understanding the Code

• Code: M25.572

• Description: Pain in left ankle and joints of left foot

• Category: Other joint disorders, not elsewhere classified

Coders assign M25.572 when the provider documents ankle pain but does not diagnose a condition like arthritis, fracture, or sprain. Because it represents a symptom, it is usually replaced once the underlying cause is confirmed.

Related ICD-10 Codes for Ankle Pain

Using the correct code ensures billing accuracy and reflects the provider’s documentation clearly.

Excludes Notes: Coding Rules

ICD-10 coding requires strict attention to Excludes notes:

• Excludes1: Codes that cannot be used together.

  • Example: M25.572 should not be coded with acute injury codes such as S93.4 (ankle sprain).

• Excludes2: Codes that may be reported together if documentation supports it.

  • Example: M25.572 can be paired with arthritis codes when pain is documented separately.

Clinical Causes of Left Ankle Pain

Understanding clinical context helps coders document accurately. Common causes include:

• Injuries: Sprains, fractures, ligament tears

• Overuse: Tendinitis, bursitis, stress fractures

• Chronic conditions: Osteoarthritis, rheumatoid arthritis, gout

• Post-surgical pain: After ankle reconstruction or replacement

• Systemic conditions: Inflammatory disorders affecting joints

When the cause is known, coders should report the specific condition code instead of M25.572.

Documentation Requirements

Strong documentation supports accurate coding. Providers should record:

• Laterality: Left, right, or unspecified

• Location: Ankle, foot, or joint-specific

• Duration: Acute or chronic

• Onset and severity: Date started, pain intensity scale

• Associated findings: Swelling, instability, numbness, restricted movement

• Tests or interventions: Imaging, labs, physical therapy

• Functional impact: How pain affects mobility or daily activities

Weak example:
“Patient has ankle pain.”

Strong example:
“Patient reports sharp left ankle pain for two weeks, worsened with walking. Pain rated 8/10. Mild swelling present. X-ray ordered.”

Common Coding Mistakes

Many denials occur because of coding errors. Frequent mistakes include:

• Using unspecified codes (M25.579) when laterality is documented

• Reporting M25.572 alongside injury codes, violating Excludes1 rules

• Coding ankle pain when a specific diagnosis is documented (e.g., osteoarthritis)

• Leaving out details like onset or severity, leading to payer rejections

• Assuming ankle pain automatically means joint pain when documentation points to soft tissue involvement

Payer Denial Example

Scenario:
A claim used M25.572 for a patient with a confirmed ankle sprai

Denial Reason:
The payer rejected it because symptom codes cannot be billed with acute injury codes.

Correct Action:
Replace M25.572 with S93.402A (sprain of unspecified ligament of left ankle, initial encounter).

Step-by-Step Coding Workflow

To assign the right ICD-10 code:

1. Identify laterality – left, right, or unspecified

2. Pinpoint location – ankle, foot, or joint

3. Check for a confirmed diagnosis – fracture, arthritis, sprain

4. Apply coding rules – Excludes1 and Excludes2 notes

5. Review documentation – onset, duration, severity, associated findings

This systematic process keeps coding consistent and compliant.

Clinical Scenarios

• Case 1: Generalized Ankle Pain
  Patient reports persistent left ankle pain without trauma.

  • Code: M25.572

• Case 2: Pain with Confirmed Arthritis
  Patient has left ankle pain due to osteoarthritis.

  • Code: M19.072 (primary osteoarthritis of left ankle)

• Case 3: Injury-Related Pain
  Patient presents with acute pain after an ankle fracture.

  • Code: S82.892A (fracture code). Do not use M25.572.

• Case 4: Chronic Post-Surgical Pain
  Patient has persistent left ankle pain after ankle surgery.

  • Code: G89.29 + M25.572 (if pain is documented separately)

Why Accurate Coding Matters

Accurate coding is not just about billing—it also:

• Ensures fair reimbursement for providers

• Supports medical necessity for tests and treatments

• Protects against audits and compliance issues

• Strengthens health data integrity for research and outcomes

FAQs

What is the ICD-10 for left ankle pain?
The code is M25.572, used when pain is documented in the left ankle without a confirmed diagnosis.

Can M25.572 be reported with fracture or sprain codes?
No. Excludes1 rules prevent symptom codes from being billed with acute injury codes.

Should I code pain or the confirmed diagnosis?
If the provider documents a condition like arthritis or fracture, use that specific code instead of M25.572.

What if documentation only states “ankle pain”?
If laterality is specified, use M25.572. If not, assign M25.579 for unspecified ankle pain.

Does chronicity affect the code?
No. The code remains M25.572, but documentation should clearly state whether pain is acute or chronic.

Conclusion

The ICD-10 for left ankle pain (M25.572) is vital for accurate documentation and billing. Coders should confirm laterality, location, severity, and any related findings before assigning the code. When a more specific diagnosis is available, it must be coded instead of M25.572. By following documentation rules, applying Excludes notes correctly, and avoiding common mistakes, coders can reduce denials, improve claim acceptance, and reflect patient care accurately.