I82.431

Acute embolism and thrombosis of right popliteal vein

Acute embolism and thrombosis of the right popliteal vein refers to the sudden formation or lodgment of a blood clot within the popliteal vein located behind the right knee. This condition is a specific form of Deep Vein Thrombosis (DVT). The popliteal vein is a major deep vein of the lower extremity, and clots in this location are classified as proximal DVTs. Proximal DVTs are clinically significant because they carry a significantly higher risk of propagating upwards into the femoral veins or breaking loose to cause a pulmonary embolism (PE), a potentially life-threatening complication, compared to distal (calf) vein thrombi. The 'acute' designation indicates that the thrombus is recently formed, typically within the last 14 days, and is often poorly attached to the vessel wall, increasing the risk of embolization.

Clinical Symptoms

  • Unilateral swelling of the right lower leg and calf
  • Pain or tenderness in the right popliteal fossa (behind the knee)
  • Pitting edema of the right ankle or lower leg
  • Increased warmth of the skin over the right calf or knee area
  • Erythema or bluish discoloration of the right lower extremity
  • Visible superficial venous distension in the right leg
  • Tenderness along the course of the deep venous system
  • Homan's sign (pain in the calf upon dorsiflexion of the foot), though non-specific
  • Possible shortness of breath or chest pain if pulmonary embolism occurs

Common Causes

  • Recent major surgery, particularly orthopedic procedures of the hip or knee
  • Prolonged immobilization or bed rest (e.g., hospitalization, long-haul travel)
  • Active malignancy or recent cancer treatment (pro-thrombotic state)
  • Trauma to the right lower extremity or popliteal region
  • Factor V Leiden mutation or other inherited thrombophilias
  • Antiphospholipid syndrome
  • Pregnancy or the postpartum period
  • Use of oral contraceptives or hormone replacement therapy
  • Obesity (Body Mass Index greater than 30)
  • Chronic venous insufficiency
  • History of previous deep vein thrombosis

Documentation & Coding Tips

Explicitly document the acuity and specific laterality of the thrombosis to ensure coding to the highest level of specificity.

Example: Patient presents with sudden onset swelling and pain in the right lower extremity. Duplex ultrasound confirms an acute embolism and thrombosis of the right popliteal vein. This is an acute event, not a chronic or subacute finding. Laterality: Right. Site: Popliteal vein. Severity: Significant swelling with 3 plus pitting edema noted.

Billing Focus: Specifying 'acute' and 'right popliteal' supports I82.431. Lack of laterality would default to an unspecified code, reducing claim accuracy and potential reimbursement.

Identify and document the clinical provoking factors or the absence thereof (provoked vs. unprovoked).

Example: The acute embolism and thrombosis of the right popliteal vein is considered provoked, following a total right knee arthroplasty performed 10 days ago. The patient has been relatively immobile during recovery. No signs of pulmonary embolism currently.

Billing Focus: Provoked status helps differentiate between temporary risk factors and idiopathic conditions, which can influence secondary codes such as Z92.1 for long-term anticoagulation.

Document the presence or absence of associated complications such as Pulmonary Embolism (PE).

Example: Diagnosis: Acute embolism and thrombosis of right popliteal vein. Patient is currently asymptomatic for chest pain or shortness of breath; CTA of the chest was negative for pulmonary embolism. This confirms an isolated lower extremity DVT.

Billing Focus: If PE is present, I26 series codes must be sequenced. Documenting the negative status prevents over-coding and clarifies the scope of the current encounter.

Note the exact anatomical location of the thrombus, distinguishing between the popliteal and more distal or proximal veins.

Example: Imaging shows a non-compressible right popliteal vein with absent flow. The thrombus does not extend into the femoral vein or downward into the tibial veins. Assessment: Isolated acute embolism and thrombosis of right popliteal vein.

Billing Focus: Precise anatomical documentation allows for the selection of I82.431 rather than I82.401 (unspecified site) or I82.441 (tibial vein).

Detail the specific anticoagulant therapy initiated, including the drug name and intended duration.

Example: Started Apixaban 10mg twice daily for 7 days followed by 5mg twice daily. This treatment is for the acute embolism and thrombosis of right popliteal vein. Plan for a 3-month course as this was a provoked event.

Billing Focus: Supports the medical necessity of follow-up visits and labs. Justifies the use of Z79.01 for long-term use of anticoagulants in subsequent visits.

Relevant CPT Codes