A 42-year-old presented gradually a posterior pain of his left knee for one month with no trauma history. He consulted our orthopedic department. Clinical examination showed no abnormality. The radiograph was normal. Sonography of the calf revealed a baker´s cyst of the knee with no sign of compressions and so we elected for medical treatment and rest advised. Three months later, the pain got worse with irradiation to the leg along with a sensation of chest tightness, reasons for which, he was transferred to our emergency department. On admission, his blood pressure was 110/52 mmHg, pulse rate 110 beats/min, respiratory rate 23 breaths/min, SaO2 96% on room air without signs of respiratory distress. The local examination found a decrease in calf bloating of his left leg with Homan´s sign positive. The D-dimer result was positive. The blood gas sampling found hypoxia-hypocapnia. The Doppler ultrasound of the left lower limp revealed a deep venous thrombosis of the popliteal vein. In the view of the strong suspicion of pulmonary embolism, computed tomography angiography of the thorax revealed a distal bilateral pulmonary embolism and so the patient was put on anticoagulant treatment and oral´s analgesics. A few days later, we performed a magnetic resonance imaging of the knee that showed a poly-lobed baker´s cyst with compression of the pedicle (A,B) prompting the patient to undergo surgery. After anesthetic preparation, we performed the resection of the cyst (C) and the intra-operative aspect showed the thrombosis of the popliteal vein (D). At a follow up of 12 months, the patient did well with no pain no dyspnea and no recurrence of Baker cyst.

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Corresponding author
Naoufal Elghoul, Orthopedic Surgery and Traumatology, Department of Orthopedic Surgery and Traumatology, Military Hospital Mohammed V (HMIMV), Rabat, Morocco (naoufal.elghoul@gmail.com)