ICD-10 Code M25.561: Pain in Right Knee
ICD-10-CM code M25.561 is used to document and bill for pain in the right knee when no more specific diagnosis has been established. It is a commonly used musculoskeletal code in primary care, orthopedics, pain management, and physical therapy settings.
This guide explains what M25.561 means, when to use it, how to code it correctly, and common documentation pitfalls—helping clinicians, coders, and billing teams ensure accuracy and compliance.
What Is ICD-10 Code M25.561?
M25.561 is a billable, specific ICD-10-CM diagnosis code that represents:
Pain in right knee
It belongs to:
- Chapter: Diseases of the musculoskeletal system and connective tissue
- Category: M25 – Other joint disorders, not elsewhere classified
This code is appropriate when a patient presents with right knee pain without a confirmed underlying condition, such as arthritis, ligament injury, or fracture.
When Should M25.561 Be Used?
M25.561 should be reported when:
- The patient’s primary complaint is pain localized to the right knee
- The cause of pain has not yet been definitively diagnosed
- The pain is documented during evaluation, follow-up, or treatment
It is commonly used during:
- Initial patient visits
- Diagnostic workups
- Symptom-based treatment plans
Once a definitive diagnosis is established (e.g., osteoarthritis, meniscal tear), the code should be updated accordingly.
Clinical Description of Right Knee Pain (M25.561)
This code captures symptom-based knee pain rather than a disease process. Providers may use it when imaging, labs, or specialist evaluations are still pending or inconclusive.
Common Symptoms Associated With M25.561
Patients may report:
- Localized pain in the right knee
- Swelling or visible inflammation
- Stiffness, especially after rest or inactivity
- Reduced range of motion
- Pain that worsens with walking, standing, or exercise
- Tenderness around the joint
Documenting these symptoms supports clinical decision-making and continuity of care.
Related ICD-10-CM Codes for Knee Pain
Selecting the correct laterality is critical for accurate coding.
| ICD-10 Code | Description |
|---|---|
| M25.561 | Pain in right knee |
| M25.562 | Pain in left knee |
| M25.569 | Pain in unspecified knee |
Best practice: Always specify laterality when known to avoid claim denials and treatment confusion.
Billing and Documentation Guidelines for M25.561
Appropriate Use for Billing
M25.561 is valid for billing when:
- Right knee pain is clearly documented in the assessment
- No more specific diagnosis is confirmed at the time of the encounter
While imaging results and detailed exam findings are helpful clinically, they are not required for billing, provided the pain is clearly documented.
Coding Guidelines and Best Practices
To code M25.561 correctly:
- Document “right knee pain” explicitly in the assessment
- Ensure laterality matches all clinical notes
- Update the diagnosis if future testing reveals a definitive condition
Pairing With G89 Pain Codes
M25.561 may be paired with G89 codes to indicate:
- Acute pain
- Chronic pain
This should be done only when the encounter specifically addresses pain management and documentation supports it.
Common Coding Mistakes to Avoid
- Incorrect laterality (right vs. left knee)
- Continuing to use M25.561 after a definitive diagnosis is made
- Using unspecified knee pain (M25.569) when laterality is known
- Inconsistent documentation across notes and claims
Avoiding these errors helps reduce denials and improves care coordination.
Authoritative Resources for ICD-10 Coding
- CMS ICD-10-CM Official Guidelines – Coding rules and updates
- WHO ICD-10 Browser – Code verification and classification reference
These resources ensure ongoing compliance with national and international standards.
Frequently Asked Questions
What does ICD-10 code M25.561 mean?
M25.561 represents pain in the right knee without a confirmed underlying diagnosis.
Is M25.561 a billable ICD-10 code?
Yes. M25.561 is a billable and specific ICD-10-CM code.
Can M25.561 be used for chronic knee pain?
Yes, and it may be paired with a G89 chronic pain code if documentation supports it.
When should M25.561 be replaced with another code?
Once a definitive diagnosis (e.g., osteoarthritis, ligament injury) is identified, a more specific ICD-10 code should be used.
What is the difference between M25.561 and M25.569?
M25.561 specifies right knee pain, while M25.569 is used when the affected knee is unspecified.
Conclusion:
ICD-10-CM code M25.561 plays a vital role in documenting and billing for right knee pain when a definitive diagnosis has not yet been established. Proper use supports accurate claims, clear clinical communication, and appropriate patient care.
