A novel synthetic material for spinal fusion: a prospective clinical trial of porous bioactive titanium metal for lumbar interbody fusion
The objective of this study was to establish the efficacy and safety of porous bioactive titanium metal for use in a spinal fusion device, based on a prospective human clinical trial. A high-strength spinal interbody fusion device was manufactured from porous titanium metal. A bioactive surface was produced by simple chemical and thermal treatment. Five patients with unstable lumbar spine disease were treated surgically using this device in a clinical trial approved by our Ethics Review Committee and the University Hospital Medical Information Network. Clinical and radiological results were reported at the minimum follow-up period of 1 year. The optimal mechanical strength and interconnected structure of the porous titanium metal were adjusted for the device. The whole surface of porous titanium metal was treated uniformly and its bioactive ability was confirmed before clinical use. Successful bony union was achieved in all cases within 6 months without the need for autologous iliac crest bone grafting. Two specific findings including an anchoring effect and gap filling were evident radiologically. All clinical parameters improved significantly after the operation and no adverse effects were encountered during the follow-up period. Although a larger and longer-term follow-up clinical study is mandatory to reach any firm conclusions, the study results show that this porous bioactive titanium metal is promising material for a spinal fusion device.
KeywordsPorous titanium metal Spinal fusion Biomaterial Clinical trial
The authors thank Hisashi Kitagaki, Tsuneo Teraoka, of Osaka Yakin Co., for manufacturing and providing the porous titanium implants. They thank Seiji Yamaguchi, of Chubu University Biomedical Sciences, for treating the material chemically. They thank Shuji Higuchi, Masanori Fukushima, Satoshi Teramukai, Kenichi Yoshimura, Toshinori Murayama, Tomoko Yokota, Erika Hirata and Harue Tada, of Kyoto University’s translational research center, for help in protocol preparation, moderation of the clinical trial and data management. They also thank Takeshi Sakamoto, Makoto Yoshida and Masahiko Miyata for radiological assessments, and Masato Ota for surgical assistance.
This study was supported by a Grant in Aid for Scientific Research from the Japan Society for the Promotion of Science (No. 19200039). No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. This manuscript has not been previously published and is not under consideration for publication elsewhere. The first two authors contributed equally to this study and preparation of this manuscript.
- 23.Otsuki B, Takemoto M, Fujibayashi S, Neo M, Kokubo T, Nakamura T (2006) Pore throat size and connectivity determine bone and tissue ingrowth into porous implants: three-dimensional micro-CT based structural analyses of porous bioactive titanium implants. Biomaterials 27:5892–5900PubMedCrossRefGoogle Scholar