title: Effect of fixation on neovascularization during bone healing.
abstract: Fixation and vascularity after bone fracture are two critical factors for successful healing, and their influences on bone healing have been studied by many researchers. This research aims to obtain three-dimensional (3D) reconstruction images of neovascularization of the soft tissues surrounding the fracture with vascular perfusion and micro-computer tomography (micro-CT) imaging, and to investigate the effect of stable fixation on neovascularization and the pattern of vascularity during the process of bone healing. To accomplish this, 36 Sprague-Dawley (SD) rats underwent mid-shaft transverse osteotomy of the right tibia. Half of them received stable fixation with a newly custom-designed external fixator (FSF, the group of fracture with stable fixation), while the rest received no fixation (FNF, the group of fracture with no fixation). The results indicated that FNF samples had more transversal vascular distribution than FSF samples; FSF samples had more longitudinal vascular distribution than FNF samples; and the spatio-temporal pattern of vascularity in FSF samples was more similar to that in the control group (CON, the group without fracture) than that in FNF samples. At the time of 2 and 4 weeks postoperatively, FNF samples had significantly higher vessel volume ratio (VV/TV), larger vessel number (VN) and higher vessel surface density (VS/TV) than CON samples. At all sacrifice times, FSF samples contained significantly higher VV/TV, VN and VS/TV values compared with FNF samples. In summary, neovascularization and its pattern are obviously influenced by the mechanical fixation. Stable fixation can promote longitudinal vascularity pattern formation, which tends to be similar to the natural vascularity pattern, and this benefits the inter-fragmentary blood fluid connectivity during bone healing process.
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Feng
authors: F
authors: Zhao
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Zhilun
authors: Z
authors: Zhou
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Yang
authors: Y
authors: Yan
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Zhen
authors: Z
authors: Yuan
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Guanzhong
authors: G
authors: Yang
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Hao
authors: H
authors: Yu
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China.
authors: Hao
authors: H
authors: Su
authors: Tianjin Medical University General Hospital, Tianjin, 300052, PR China.
authors: Tao
authors: T
authors: Zhang
authors: Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, 37 Xueyuan Road, Haidian District, Beijing, 100191, PR China. Electronic address: yubofan@buaa.edu.cn.
authors: Yubo
authors: Y
authors: Fan
mesh_terms: D000818:Animals; D001808:Blood Vessels / Q000502:physiology; D005592:Fracture Fixation; D017102:Fracture Healing; D021621:Imaging, Three-Dimensional; D018919:Neovascularization, Physiologic; D051381:Rats; D017207:Rats, Sprague-Dawley; D013977:Tibia / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000502:physiology* / Q000601:surgery; D055114:X-Ray Microtomography
keywords: External fixator; Micro-CT imaging; Neovascularization; Stable fixation; Vascularity pattern