Angiogenic and Osteogenic Responses Related to Femoral Neck Fractures Treated at Different Fracture-To-Surgery Intervals in a Canine Model

摘要

The aim of current prospective study was to investigate systemic changes in angiogenic factor VEGF and osteogenic factor IGF-1 and the local expression of BMP-2 and Runx-2 in femoral neck fractures of canines that were treated at different fracture-to-surgery intervals. About 24 dogs had surgically induced femoral neck fractures which were divided randomly and equally into three groups. In group A, the fractures were reduced and stabilized by paralleled pins immediately while they were managed 3 days later in group B and 3 weeks later in group C. Pre and post-operative peripheral serum was prepared for detection of systemic concentrations of VEGF and IGF-1 via ELISA Method. Postoperative radiological and histological examinations were employed to observe fracture union and occurrence of Osteonecrosis of the Femoral Head (ONFH). Local expressions of BMP-2 and Runx-2 were detected via immunohistochemical staining. Another 2 dogs had fractures untreated for negative control. Systemic changes in VEGF and IGF-1 were shown to share similarities when fractures were treated at different fracture-to-surgery intervals or left untreated. Moreover, the local expression of BMP-2 and Runx-2 were not statistically different in all treated and untreated animals. The manner of the response of systemic expression of VEGF and IGF-1 and local expression of BMP-2 and Runx-2 showed great similarity when femoral neck fractures were treated at different fracture-to-surgery intervals. Angiogenic and osteogenic responses might not be responsible for fracture-induced ONFH.