Significance of expression of nerve growth factor in femoral shaft fracture combined with traumatic brain injury

Abstract

Objective To explore the relationship between fracture healing and level variation of nerve growth factor (NGF) in the serum of patients with femoral shaft fracture combined with traumatic brain injury. Methods Sixty-four patients with femoral shaft fracture were divided into simple fracture group (n=32) and composited injured group (fracture combined with traumatic brain injury, n=32). Treatments like open reduction and internal fixation, or fixation with unreamed tibial nail were performed according to the patient's condition. Two-site enzyme-linked immunosorbent assy (ELISA) was employed to detect the serum level of NGF 1, 7, 14 and 21 d after injury; and correlation analysis of clinical healing time of fracture and serum level of NGF was performed on the 1 d of injury in the composited injured group. The clinical healing time of fracture between the 2 groups were compared.Results The clinical healing time in the composited injured group (62.88±5.99) was shorter than that in the simple fracture group (82.47±3.07, t=-16.473, P=0.000); and there was a high negative correlation between the clinical healing time of fracture and serum level of NGF on the 1 d of injury in the composited injured group(r=-0.966, P=0.000). The serum level of NGF in the composited injured group was higher than that in the simple group at each time points (P＜0.05), and the serum level of NGF in the 2 groups peaked on the 14th d of injury; and decreased gradually. Conclusion Serum level of NGF increases in the early phase in patients with femoral shaft fracture combined with traumatic brain injury and remains at a high level for the first 2 weeks, which may play an important role in promoting fracture healing. Key words: Femoral shaft fracture; Nerve growth factor; Traumatic brain injury; Fracture healing