Phlebitis and thombophlb of unspecified calf muscular vein

This diagnosis code signifies inflammation of a vein accompanied by thrombus formation, specifically located within the muscular veins of an unspecified calf. It indicates a deep vein thrombosis (DVT) affecting the lower leg musculature, without further specification of laterality (left or right).

Apply this code when documentation clearly states phlebitis and thrombophlebitis of a calf muscular vein, but the specific calf (left or right) is not identified. This is appropriate for DVT affecting the gastrocnemius or soleus veins when laterality is unknown. Supporting documentation includes physician notes detailing symptoms like calf pain, swelling, and tenderness, along with imaging reports (e.g., ultrasound) confirming the presence of a thrombus in an unspecified calf muscular vein.

• Only use this code when laterality is genuinely unspecified in the medical record.
• Avoid using this code if the documentation specifies "right calf" or "left calf"; instead, use the more specific codes (I80.251 or I80.252).
• Ensure the documentation differentiates muscular vein involvement from superficial or other deep vein involvement in the calf.