Pseudothrombophlebitis syndrome is a clinical condition where there are signs and symptoms of phlebitis in the absence of a thrombophlebitis lesion. Symptoms include pain, swelling, erythema and tenderness evolving over hours or days. It is often associated with the rupture or dissection of a popliteal cyst otherwise known as a Baker's cyst, although it can be associated with other disorders such as the arthritides. It may also occur as an orthopaedic surgical complication, secondary to trauma or as a presentation of septic arthritis. It is crucial to differentiate this condition from deep vein thrombosis as the treatment for DVT can cause adverse effects in patients with pseudothrombophlebitis.