Viscosupplementation by intra-articular (i.a.) injection of the non-
sulfated glycosaminoglycan (GAG)
hyaluronic acid (HA) is a
conservative therapy widely accepted in clinical practice for the management of
osteoarthritis (OA) and
joint diseases. The aim of
viscosupplementation is to restore the rheological properties of the synovial fluid to relieve joint
inflammation and
pain and improve joint function through a chondroprotective effect. However, there is a range of
hyaluronic acid products for OA that differ in preparation, molecular weight, rheological characteristics and concentration, and different i.a. formulations are more suited to particular patient populations and clinical situations, in part because of anatomical differences between joints. This paper focuses on innovative hybrid cooperative complexes of high and low molecular weight
hyaluronic acid (HA-HL) and
hyaluronic acid plus
sodium chondroitin (HA-SC) that have been developed. Both products are formulated with pharmaceutical-grade, highly purified
hyaluronic acid obtained with a multi-step biofermentation process, with properties that make them suitable across a range of degenerative
joint diseases. They represent progress in building on the symptomatic and functional benefits of
viscosupplementation in
joint disease, with the additional beneficial effect of treating the patient with a high concentration of GAGs by a low number of
injections. Here, we review the clinical evidence for the efficacy of a hybrid cooperative compound of HA-HL in various degenerative
joint diseases, which suggests a synergistic effect of the different molecular weight hyaluronans that together more closely mimic the physiological composition of synovial fluid. Similarly, the evidence shows that HA-SC is safe, effective, and well tolerated in hip OA, with rapid and clinically significant improvements in
pain symptoms and functionality. Such innovations in
viscosupplementation expand the usefulness of the modality in the management of OA and other
joint diseases, complemented by a lack of systemic or local side effects that allow the concurrent use of other drugs if needed.