Effect of vacuum-assisted closure combined with open bone grafting to promote rabbit bone graft vascularization

Patients with composite bone non-union and soft tissue defects are difficult to treat. Vacuum-assisted closure (VAC) combined with open bone grafting is one of the most effective treatments at present. The aim of the present study was to preliminarily investigate the effect and mechanism of VAC combined with open bone grafting to promote rabbit bone graft vascularization, and to propose a theoretical basis for clinical work.

Twenty-four New Zealand white rabbits were randomly divided into an experimental and a control group. Allogeneic bones were grafted and banded with the proximal femur with a suture. The experimental group had VAC whereas the control group had normal wound closure. The bone vascularization rate was compared based on X-ray imaging, fluorescent bone labeling (labeled tetracycline hydrochloride and calcein), calcium content in the callus, and expression of fibroblast growth factor-2 (FGF-2) in bone allografts by Western blot analysis at the 4th, 8th, and 12th week after surgery.

At the 4th, 8th, and 12th week after surgery, the results of the tests demonstrated that the callus was larger, contained more calcium (p<0.05), and expressed FGF-2 at higher levels (p<0.05) in the experimental group than in the control group. Fluorescent bone labeling showed the distance between the two fluorescent ribbons was significantly shorter in the control group than in the experimental group at the 8th and 12th week after surgery.

VAC combined with open bone grafting promoted rabbit bone graft vascularization.