Foreign body giant cell reaction due to Durolane (hyaluronic acid derivative) injection - A case report.

Osteoarthritis can be treated with hyaluronic acid derivatives, such as Durolane manufactured by Bioventus (Hill, 2017), particularly when conventional treatments prove ineffective. In osteoarthritic joints, the synovial fluid has a lower concentration of hyaluronic acid compared to healthy joints. Intra-articular therapy with exogenous hyaluronic acid can improve viscoelastic properties, enhance chondrocyte synthesis, reduce cartilage degradation, and alleviate pain associated with osteoarthritis (Migliore and Procopio in Clin Cases Miner Bone Metab. 12:31-3, 2015). This report describes a unique case where a patient, following Durolane administration, presented with an intraosseous foreign body giant cell reaction. A 2.5-cm lesion was identified on MRI, initially raising concerns for metastatic disease or multiple myeloma. Subsequent IR CT-guided biopsy confirmed a diagnosis of "foreign body giant cell reaction to gel," linked to the Durolane injection. This case presents a contribution to the literature due to the scarcity of documented instances where Durolane injection leads to an intraosseous foreign body giant cell reaction resembling metastatic disease. While a solitary intraosseous pseudotumor, reportedly due to viscosupplement injection, has been published, it differs in both location (hip vs. knee) and imaging characteristics from the presented case. The manifestation of a foreign body giant cell reaction after Durolane injection, mimicking malignant osseous lesions, merits attention among practitioners. This case underscores the necessity for further research into potential adverse reactions associated with hyaluronic acid derivatives.