A 67-year-old man presented with acute monoarthritis of the right knee. Aspiration was carried out under aseptic precautions. This yielded a milky appearing fluid. Polarized microscopic examination confirmed uric acid crystals. The patient had a history of trauma to the joint. Acute monoarthritis of the knee can occur due to gout. Chylous effusions in the knee are rare. This combination of findings in the same joint has not been described in the literature. We emphasise the importance of history of trauma in acute monoarthritis. We discuss the unusual features of this case.