275 patients were compiled from two initial studies that lasted 3 years to assess the effectiveness of glucosamine sulphate treatment in osteoarthritis (OA). This retrospective study included patients who had undergone treatment with placebo or glucosamine sulphate, 1500 mg once daily, between 12 and 36 months. Patients were followed-up 5 years following the cessation of the original study to determine the rate of total joint replacement (TJR). Results indicated that glucosamine sulphate treatment reduced the risk of TJR in patients with OA. The relative risk was 0.43 in comparison the patients on placebo treatment.