BACKGROUND: Osteoporosis and its associated fractures have become increasingly common in Korea because of increasing population age. Both alendronate (ALN) and raloxifene (RLX) can treat and prevent new vertebral fractures. The purpose of this study was to compare the effects of combined alendronate and raloxifene therapy with alendronate therapy alone in osteoporotic patients that had been treated by percutaneous vertebroplasty. METHODS: We analyzed 40 patients older than 50 years, and performed percutaneous vertebroplasty due to osteoporotic compression fractures. Twenty patients received alendronate only at 70 microgram/week, and the other 20 patients received combined alendronate at 70 microgram/week and raloxifene at 60 microgram/day. At baseline and after 3 and 6 months, we measured the bone mineral density (BMD) of the lumbar spine and femoral neck. RESULTS: On average, the lumbar spine BMD increased by 7.1 and 8.7% from baseline in the ALN and in the ALN + RLX group. The increase in femoral neck BMD in the ALN + RLX group (8.0%) was greater than the 5.6% increase in the ALN group (P = 0.02). CONCLUSIONS: Combined RLX and ALN therapy is more effective than ALN therapy alone in terms of increasing the femoral neck BMD in osteoporotic vertebral compression fracture patients treated by percutaneous vertebroplasty.