Intra-articular hyaluronic acid injections for knee osteoarthritis

Knee osteoarthritis is a common but often difficult problem to manage in pr imary care. Traditional nonsurgical management, consisting of lifestyle mod ification, physical therapy and pharmacologic therapy (e.g., analgesics, an ti-inflammatory medications), is often ineffective or leaves residual sympt oms, Viscosupplementation is a newly available option for patients with sym ptomatic knee osteoarthritis that involves a series of intra-articular inje ctions of hyaluronic acid, The exact mechanism of action is unclear, althou gh increasing the viscoelasticity of the synovial fluid appears to play a r ole. Clinical experience and studies of the two hyaluronic acid products av ailable, hyaluronan and hylan G-F: 20, are inconclusive but seem to indicat e beneficial effects with minimal adverse reactions in a significant number of patients. The exact indications for viscosupplementation are still evol ving, but it currently can be considered for use in patients who have signi ficant residual symptoms despite traditional nonpharmacologic: and pharmaco logic treatments. In addition, patients who are intolerant of traditional t reatments (e.g,, gastrointestinal problems related to anti-inflammatory med ications) can be considered for these injections. family physicians with th e ability to perform intra-articular knee injections should consider them a n option in patients with symptomatic knee osteoarthritis.