What is the ICD-10 (International Classification of Diseases, 10th Revision) code for effusion of the right knee?

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ICD-10 Code for Right Knee Effusion

The appropriate ICD-10 code for effusion of the right knee is M25.461 (Joint effusion, right knee).

Understanding Knee Effusion

  • Knee effusion represents an abnormal accumulation of fluid in or around the knee joint that may be detected clinically or through imaging studies 1
  • Effusion can be visualized on various imaging modalities including radiographs, ultrasound, and MRI, with ultrasound being particularly useful for confirming suspected effusions and potentially guiding aspiration 1
  • A cross-table lateral view with a horizontal beam on radiographs can enable visualization of joint effusion and potential lipohemarthrosis in cases of acute trauma 1

Clinical Significance of Knee Effusion

  • Knee effusion may indicate underlying joint inflammation, irritation, or injury and requires objective monitoring for clinical decision-making 2
  • Effusion can be associated with various conditions including trauma, overuse syndromes, arthritis, infection, crystal deposition, and tumor 3
  • Studies have shown that knee joint effusion has independent associations with knee pain in older adults, with different patterns of pain depending on the location of the effusion 4
  • Knee effusion detected by ultrasonography may be an indicator of the progression of early-stage knee osteoarthritis, particularly in overweight women 5

Diagnostic Approaches

  • Ultrasound can be used to quantify the degree of effusion and is as accurate as MRI in diagnosing popliteal cysts and detecting cyst rupture 1
  • For persistent effusions, joint aspiration may be indicated if there is concern for crystal disease or infection 6
  • Ultrasound or fluoroscopically guided joint aspiration can improve accuracy, especially when targeting specific compartments or dealing with small effusions 6

Coding Considerations

  • When coding knee effusion, it's important to specify laterality (right vs. left) to ensure accurate documentation 7
  • The transition from ICD-9 to ICD-10 coding has generally shown relatively small discontinuities for most musculoskeletal conditions, but proper specificity in coding is essential 7
  • The correct ICD-10 code M25.461 specifically identifies the condition as affecting the right knee, which is critical for accurate medical documentation and billing 7

Management Implications

  • Identification and documentation of knee effusion using the correct ICD-10 code is important for appropriate treatment planning and monitoring 6
  • Following aspiration of persistent effusions, corticosteroid injections may be considered, which can result in reduction of synovitis in approximately two-thirds of patients 6
  • Ultrasound can be used not only for diagnosis but also to guide potential aspiration procedures 1, 6

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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