Mechanisms Underlying Normal Fracture Healing and Risk Factors for Delayed Healing

Abstract

Purpose of review: Substantial advances have been made in understanding the biological basis of fracture healing. Yet, it is unclear whether the presence of osteoporosis or prior or current osteoporosis therapy influences the healing process or is associated with impaired healing. This review discusses the normal process of fracture healing and the role of osteoporosis and patient-specific factors in relation to fracture repair.

Recent findings: The definitive association of osteoporosis to impaired fracture healing remains inconclusive because of limited evidence addressing this point. eStudies testing anabolic agents in preclinical models of ovariectomized animals with induced fractures have produced mostly positive findings showing enhanced fracture repair. Prospective human clinical trials, although few in number and limited in design and to testing only one anabolic agent, have similarly yielded modestly favorable results. Interest is high for exploring currently available osteoporosis therapies for efficacy in fracture repair. Definitive data supporting their efficacy are essential in achieving approval for this indication.

Keywords: Atypical femoral fracture; Bisphosphonates; Denosumab; Dickkopf-1; Estrogen; Fracture healing; Osteoporosis; PTH-related peptide; Parathyroid hormone (PTH); Raloxifene; Risk factors; Sclerostin.