Septic knee arthritis after intra-articular hyaluronate injection. Two case reports.

Intraarticular sodium hyaluronate injection to treat osteoarthritis is associated with minor side effects. Infections seem uncommon. We report two cases of septic knee arthritis. One patient was an 80-year-old woman who was admitted for Staphylococcus aureus knee arthritis after several intraarticular injections of sodium hyaluronate and corticosteroids. In the other patient, a 78-year-old woman, Neisseria mucosa knee arthritis occurred after a single sodium hyaluronate injection. Faultless aseptic technique is essential when administering hyaluronate viscosupplementation. Patients should be informed of the risk of septic arthritis.