Synovial knee fistula

Postarthroscopy knee fistulae may lead to prolonged morbidity. A 62-year-old man presented with a synovial knee fistula 4 weeks after knee arthroscopy, which was confirmed by magnetic resonance imaging. He was treated with antibiotics and knee immobilization that resulted in closure of the fistula. He then developed recurrent septic knee effusion that required arthroscopic washout, further antibiotic treatment, and physiotherapy. The patient's clinical condition resolved after a further 6 weeks. This case shows that not all fistulae resolve spontaneously; they may lead to prolonged morbidity and necessitate further treatment. We also wish to note that magnetic resonance imaging is a useful diagnostic tool in place of the traditional sinogram.