Parathyroid hormone – possible future drug for orthopedic surgery

Ramunė Aleksynienė^{1, 2}, Ivan Hvid³

¹Institute of Experimental Clinical Research, Aarhus University, Denmark, ²Department of Orthopedics, Kaunas University of Medicine Hospital, Lithuania, ³Department of Orthopedics, Aarhus University Hospital, Denmark

Key words: parathyroid hormone, orthopedics.

Summary. Parathyroid hormone naturally secreted by the parathyroid glands is a potent anabolic agent for bone. Parathyroid hormone is primarily thought of as a catabolic protein involved in the physiologic release of calcium from bone. Whereas during recent years, a number of animal studies and clinical trials have demonstrated that intermittent parathyroid hormone administration induces anabolic effects on both cancellous and cortical bone, enhances bone mass and increases mechanical strength of the bones. Most of the studies, both animal and human, have addressed the treatment of osteoporosis and parathyroid hormone represents an important new advance in the therapy of osteoporosis. Few studies have investigated the effect of intermittent parathyroid hormone treatment in the field of orthopedics on fracture healing and fixation of orthopedic implants. The results of those studies indicated an enhancement of fracture healing, faster bone repair and better fixation of the implant. Recently there were few animal studies started to investigate the effects of parathyroid hormone treatment on bone formation in regenerated and surrounding bone of distracted callus during limb lengthening. Distraction osteogenesis is a technique for bone lengthening that is widely used clinically and experimentally. Newly forming bone during distraction osteogenesis is expected to be an appropriate pattern for parathyroid hormone anabolic effect. Preclinical studies as well as clinical trials suggest that parathyroid hormone might be useful as a stimulator of bone formation whereas a lot of questions regarding parathyroid hormone therapy remain unanswered and require further experimental studies and investigations.

Correspondence to R. Aleksynienė, Department of Orthopedics, Aalborg Hospital, P. O. Box 365, 9100 Aalborg, Denmark E-mail: ramunealeks@vision.kmu.lt

Received 22 April 2004, accepted 28 June 2004