'Old drugs for new applications': can orthopedic research benefit from this strategy?

New drug exploration is difficult in a clinical setting and the development of new drugs may be costly and time consuming. With further research into the pathological mechanisms and etiology of diseases as well as the rapid development of biological techniques, many 'old drugs' that have been applied in clinics may have new therapeutic functions which may shed light on clinical management. Based on this, we have investigated the 'old drugs for new applications' strategy in pharmacology which may be less expensive and more efficient in the clinical setting. In this paper we have explored and illustrated the potential applications of 'old drugs' for the treatment of orthopedic diseases, especially in arthritis and osteoporosis therapy.