Knee Osteoarthritis is a common condition affecting many middle aged adults which leads to pain, loss of range of motion, and decreased function. Physical Therapy remains the primary choice for conservative treatment, but often these treatments are combined with injections to the knee joint. Corticosteroids are an inexpensive injection designed to reduce pain and inflammation in the knee, but Hyaluronic Acid injections such as Synvisc are also on the rise. These injections claim to cushion and lubricate the knee joint leading to reduced pain and improved function. One downside of these injections is their cost ($250-$1000 per injection) which is often not covered by insurance. In addition, the research on these injections has been compared to saline (placebo) injections instead of a head to head comparison with the corticosteroid.
Recently an article in the Journal of Bone and Joint Surgery examined the impact of a single corticosteroid or hyaluronic acid injection on 99 patients with knee osteoarthritis (Tammachote et al. 2016). Patients were randomized to receive one of the two injections then followed over 6 months. As you can see from the graph above both groups demonstrated similar outcomes in pain, function, and range of motion at 6 months. Differences were noted in the short term with decreased pain and improved function noted in the first two weeks in the patients receiving the corticosteroid. The authors called into question the cost of these expensive injections compared to the less expensive corticosteroid.