Acute Pseudoseptic Arthritis after Intra-Articular Sodium Hyaluronate Injection: A Case Report and Literature Review

Purpose: This report describes the case of 59-year-old woman with right medial compartment knee osteoarthritis (OA) who experienced an unusual adverse reaction to intra-articular sodium hyaluronate injection. Methods: The patient received an intra-articular sodium hyaluronate injection for treatment of knee OA. Ten days after injection, she experienced severe pain in her right knee wherein laboratory test results showed inflammatory profiles that could not rule out septic arthritis. Joint lavage was performed, after which the patient was monitored for any changes in her symptoms or laboratory test results. Results: The patient experienced severe pain in her right knee after intra-articular sodium hyaluronate injection. Additionally, laboratory test results showed inflammatory profiles that could not rule out septic arthritis. One month after joint lavage, the patient's symptoms resolved, and her laboratory test results returned to normal range. Conclusions: An inflammatory flare could occur as an adverse effect of intra-articular sodium hyaluronate injection, mimicking septic arthritis. Importantly, both physicians and patients should be aware of this potential reaction, particularly, patients should report any unusual symptoms to their healthcare provider.