Evaluation of an artificial vertebral body fabricated by a tantalum-coated porous titanium scaffold for lumbar vertebral defect repair in rabbits

Zhensheng Ma,Lin Wang,Yang Zhang,Xiaojiang Yang,Xiangyu Ma,Zhao Yang,Xinxin Wen,Tiancheng Ma,Wei Lei,Jian Wang,Faqi Wang,Lei Shi,Yafei Feng

doi:10.1038/s41598-018-27182-x

Abstract

Tantalum (Ta)-coated porous Ti-6A1-4V scaffolds have better bioactivity than Ti-6A1-4V scaffolds; however, their bioperformance as an artificial vertebral body (AVB) is unknown. In the present study, we combined a Ta-coated Ti-6A1-4V scaffold with rabbit bone marrow stromal cells (BMSCs) for tissue-engineered AVB (TEAVB) construction and evaluated the healing and fusion efficacy of this scaffold in lumbar vertebral defects after corpectomy in rabbits. The results showed that BMSCs on the surface of the Ta-coated Ti scaffolds proliferated better than BMSCs on Ti scaffolds. Histomorphometry showed better bone formation when using Ta-coated TEAVBs than that with Ti TEAVBs at both 8 and 12 weeks after implantation. In addition, the vertical and rotational stiffness results showed that, compared with uncoated TEAVBs, Ta-coated TEAVBs enhanced rabbit lumbar vertebral defect repair. Our findings demonstrate that Ta-coated TEAVBs have better healing and fusion efficacy than Ti TEAVBs in rabbit lumbar vertebral defects, which indicates their good prospects for clinical application.

Highlights

Vertebral corpectomy and anterior spinal decompression is a major surgical method for spine diseases, including spinal tumors, spinal tuberculosis and unstable burst vertebral fracture, which occasionally cause severe vertebral body destruction and result in neural impingement and spinal instability[1,2,3]
The porous Ti-6A1-4V scaffold vector with a diamond molecular structure was made with direct metal rapid prototyping (RP) technology
Both pore structures and gap sizes of the porous Ti-6A1-4V scaffolds were basically consistent between pre- and postcoating, implying the favorable characteristics of the interconnected pore structure, which could facilitate cell adhesion, cell proliferation, tissue ingrowth, and the revascularization of scaffold vectors during defect repair (Fig. 1)

Summary

Introduction

Vertebral corpectomy and anterior spinal decompression is a major surgical method for spine diseases, including spinal tumors, spinal tuberculosis and unstable burst vertebral fracture, which occasionally cause severe vertebral body destruction and result in neural impingement and spinal instability[1,2,3]. The objective of this study was to fabricate a Ta-coated Ti-6A1-4V scaffold with a controlled porous structure using EBM and chemical vapor deposition (CVD) to construct a tissue-engineered AVB (TEAVB) combined with rabbit BMSCs and to evaluate the healing and fusion efficacy of TEAVB in a large lumbar vertebral defect after corpectomy in a rabbit model. This is the first study to use a Ta-coated Ti-6A1-4V TEAVB for the repair of intact vertebral defects

Objectives

Methods

Results

Conclusion