Study Design. In vivo assessment of a novel artificial vertebral body fabricated by electron beam melting (EBM) for cervical vertebral body replacement in a sheep model.
Objective. To investigate the feasibility of a novel artificial vertebral body: a “self-stabilizing artificial vertebral body” (SSAVB) fabricated by EBM in a sheep model.
Summary of Background Data. Artificial vertebral body is widely used for vertebral body replacement and spinal fusion, but research on an artificial vertebral body fabricated by EBM has not been reported.
Methods. An SSAVB made of porous Ti6Al4V was implanted into a sheep cervical spine to replace the C4 vertebral body for 6 and 12 weeks. Bone ingrowth and implant stability were radiologically evaluated, and histological and biomechanical tests were performed.
Results. No screw loosening, implant dislocation, or bone fractures occurred during the experimental period. A significant difference (P = 0.001) in bone ingrowth between the 6- and 12-week groups was noted. Comparison of the range of motion of C3–C5 segments between the in vivo group and the control groups (intact C2–C6 segment and fresh sheep cervical spines from C2 to C6 segments that underwent C4 subtotal corpectomy with the posterior vertebral wall retention by SSAVB implantation) suggests that the implant can stably replace this area of the cervical spine.
Conclusion. The open porous structure of Ti6Al4V fabricated by EBM facilitated bone ingrowth and the SSAVB can maintain cervical spine stability of the sheep. A porous metal implant can be used for load-bearing applications in a sheep model. It is hoped that these results will stimulate further study in human.
Level of Evidence: 4
To date, research-related experiments on artificial vertebral body fabricated by electron beam melting (EBM) has not been reported. This article investigates the feasibility of a novel artificial vertebral body without an additional anterior plate or a posterior internal fixation named self-stabilizing artificial vertebral body fabricated by EBM in a sheep model.
From the Department of Orthopedics, Peking University Third Hospital, Haidian District, Beijing, China.
Address correspondence and reprint requests to Zhongjun Liu, MD, or Hong Cai, MD, Department of Orthopedics, Peking University Third Hospital, 49 North Garden Rd., Haidian District, Beijing, China; E-mail: firstname.lastname@example.org or email@example.com
Acknowledgment date: October 22, 2013. First revision date: November 25, 2013. Second revision date: December 19, 2013. Acceptance date: January 2, 2014.
The device(s)/drug(s) that is/are the subject of this manuscript is/are not FDA-approved for this indication and is/are not commercially available in the United States.
My manuscript includes unlabeled/investigational uses of the products/devices listed below and the status of these is disclosed in the manuscript: self-stabilizing artificial vertebral body.
Project of Scientific and Technical Plan of Beijing (Program title: The Development of Orthopaedic Metal Implant Fabricated by Electron Beam Melting. Program number: http://www.bjkw.gov.cn) funds were received to support this work.
Relevant financial activities outside the submitted work: grant.