ICD-10 Code I87.099 – Postthrombotic syndrome with other complications of unspecified lower extremity (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code I87.099 – Postthrombotic syndrome with other complications of unspecified lower extremity
What it is
I87.099 identifies postthrombotic syndrome affecting an unspecified lower extremity, with complications other than the standard venous sequelae. Use it when a prior deep vein thrombosis has led to ongoing limb problems, but the affected side is not documented.
Clinical signs
Typical findings include chronic leg swelling, pain, heaviness, skin changes, or venous insufficiency after a previous thrombotic event. Clinical features vary; refer to documentation.
When to use this code
Use this code when the record links the current lower-extremity condition to prior thrombosis and the documentation describes additional complications. It is appropriate when the provider does not specify right or left leg. If the note only says “history of DVT” without current sequelae, check documentation.
Do not use for
Do not use this code for acute deep vein thrombosis, uncomplicated venous insufficiency, or postthrombotic syndrome with a documented right or left lower extremity. Check documentation if the complication is not clearly described.
Coding tip
Confirm both the postthrombotic relationship and the unspecified laterality before assigning I87.099.