Study Summary

Two hundred twenty-two patients with symptomatic knee osteoarthritis and without severe joint space narrowing were randomized to receive either intravenous zoledronic acid (5 mg annually, n=113) or placebo (n=109). The primary outcome of interest was the risk of total knee replacement. Secondary outcomes included the incidence of total knee replacement in the study knee, total knee replacement in the contralateral knee, and changes in knee pain scores over time. Outcomes were assessed over a mean follow-up period of seven years. Overall, the study found that zoledronic acid was not protective against total knee replacement. In fact, during the first two years, patients receiving zoledronic acid had a significantly higher risk of total knee replacement compared to placebo. However, after the trial period, the risk was similar between groups. These findings suggest that zoledronic acid is not beneficial in preventing knee replacement in this patient population and may even accelerate the need for surgery in the short term.