Changes of serum GH/IGF- I axis and related clinical significance following traumatic long bone fracture

Abstract

Objective To investigate the changes of serum growth hormone （GH）/insulin-like growth factor- I （IGF- I ） in patients with traumatic long bone fractures and the related clinical signifi- cance. Methods Twenty-one patients with traumatic long bone fractures from the same trauma care center treated between November 2009 and April 2010 were enrolled in the study. There were 14 males and 7 females, at age range of 22-60 years （mean 45.0 years）. Seventeen patients （81%） were with closed trauma and four （19%） with open trauma. Enzyme Linked Immunoadsorbent Assay （ELISA） was used to determine the levels of serum GH and IGF- I within 14 days after fractures and the relationship between changes of GH-IGF- I axis and injury severity score （ISS） was further analyzed. Eight patients with normal GH/IGF- I were set as control group. Results The GH level in the peripheral blood was significantly higher at day 1 after fractures （P 〈 0.05 ）, and rapidly declined and stabilized at day 5 compared with the control group. The GH level in the patients with ISS≥ 18 points was significantly higher than that in those with ISS 〈 18 points at day 1 after fractures （P 〈0.05）. The IGF- I level in the peripheral blood in the patients with ISS≥ 18 points was significantly higher than that in those with ISS 〈 18 points at days 5-10 after fractures （P 〈 0.05）. Conclusion The hypothalamus GH-IGF- I axis plays an important role in early metabolism and fracture healing during the acute phase of traumatic long bone fractures. Key words: Fractures, extremities; Growth hormone; Insulin-like growth factor- I